I am trying to create a data table using the Lightning Datatable component and cannot seem to get the values to bind to the table.  The values are coming from a wrapper class on the controller that is pulling the information correctly and I can see the values I want in the console log of the test page, but they never populate in the table itself.  Please see my code below.  Any help would be appreciated.

Controller:

@auraEnabled
public static List<allActivityWrapper> getAllActivities(string parentId) {
  set<Id> taskRelationIds = new set<Id>();
  set<Id> eventRelationIds = new set<Id>();
system.debug('parent Id is '+parentId);
  set<taskRelation> taskRelations = new set<taskRelation>();
  set<eventRelation> eventRelations = new set<eventRelation>();
    List<taskRelation> tskRel = [select taskId, relation.Name from taskRelation where accountId = :parentId and isWhat = false order by createdDate asc];
    for(taskRelation tr: tskRel) {
      taskRelationIds.add(tr.taskId);
      taskRelations.add(tr);
    }
    system.debug('taskRelations list is '+taskRelations.size());
    List<eventRelation> evtRel = [select eventId, relation.Name from eventRelation where accountId = :parentId and isInvitee = false order by createdDate asc];
    for(eventRelation ev: evtRel) {
      eventRelationIds.add(ev.eventId);
      eventRelations.add(ev);
    }
    system.debug('eventRelations list is '+eventRelations.size());
    Id usrId = UserInfo.getUserId();
    string taskQuery = 'SELECT Id, Activity_Type__c, CreatedDate,  who.Name, Meeting_Type__c, Subject, Short_Description__c, ActivityDate, Description, Activity_Status__c, Owner.Name, Financial_Account__c, ActivityRelation__c, WhoId, Who.FirstName, Who.LastName  FROM task WHERE (Firm__c = :parentId OR whatId = :parentId or Id in :taskRelationIds) order by ActivityDate Desc';
    System.debug('****** task query is'+taskQuery);
    string eventQuery = 'SELECT Id, Activity_Type__c,recordType.name, who.Name, CreatedDate, Meeting_Type__c, Subject, Short_Description__c, StartDateTime, Description, Activity_Status__c, Owner.Name,  Financial_Account__c, ActivityRelation__c, WhoId, Who.FirstName, Who.LastName  FROM event  WHERE (Firm__c = :parentId OR whatId = :parentId or Id in :eventRelationIds) order by StartDateTime Desc';
    System.debug('****** event query is'+eventQuery);
    integer tableList = 750;
    string contactName = '';
    List<allActivityWrapper> allActivityList = new List<allActivityWrapper>();

    List<Task> taskList = Database.Query(taskQuery);
    List<event> eventList = Database.Query(eventQuery);
    System.debug('****** task list size is '+taskList.size());
    System.debug('****** event list size is '+eventList.size());
    integer totalListSize = taskList.Size() + eventList.Size() ;
    if(totalListSize < tableList){
      tableList = totalListSize;
    }
    system.debug('allActivityList 1 is '+allActivityList.size());
    for(task t:taskList){
      if(t.whoId == Null){
        contactName = 'No Contact';
      }else{
        contactName = t.who.name;
      }
      allActivityList.add(new allActivityWrapper(t, contactName));
    }
    system.debug('allActivityList 2 is '+allActivityList.size());
     Integer i = 0;
     for(event e:eventList){
       while (i < allActivityList.size()) {
         system.debug('event is '+e.StartDateTime +' task is '+ allActivityList[i].actCompareDate);
                   if (e.StartDateTime > allActivityList[i].actCompareDate) {
                     system.debug('event being entered is '+e.Id);
                     if(e.whoId == Null){
                       contactName = 'No Contact';
                     }else{
                       contactName = e.who.name;
                     }
                       allActivityList.add(i, new allActivityWrapper(e, contactName ));
                       break;
                   }
               i++;
          }
       }
       system.debug('allActivityList 3 is '+allActivityList.size());
    for(allActivityWrapper a: allActivityList){
      system.debug('Activity List Date is '+a.actDueDate+' name is '+a.actPrimaryContact+' id is '+a.actId);
    }
    return allActivityList;
}

public class allActivityWrapper{
    @AuraEnabled public string actId {get; set;}
    @AuraEnabled public string actLink {get; set;}
    @AuraEnabled public string actType {get; set;}
    @AuraEnabled public string actSubType {get; set;}
    @AuraEnabled public string actSubject {get; set;}
    @AuraEnabled public string actAssigned {get; set;}
    @AuraEnabled public string actFullDesc {get; set;}
    @AuraEnabled public string actPrimaryContact {get; set;}
    @AuraEnabled public string actDueDate {get; set;}
    @AuraEnabled public datetime actCompareDate {get; set;}
    @AuraEnabled public string actOwner {get; set;}

    public allActivityWrapper(Task awTask, string contactName){
        actId = awTask.Id;
        actLink ='View';
        actType = awTask.Activity_Type__c;
        actSubType  = awTask.Meeting_Type__c;
        actSubject = awTask.Subject;
        actDueDate = String.ValueOf(awTask.CreatedDate);
        actCompareDate = awTask.ActivityDate;
        actAssigned = awTask.Owner.Name;
        actFullDesc  = awTask.Short_Description__c;
        actPrimaryContact = contactName;
        actOwner = awTask.Owner.Name;
    }

    public allActivityWrapper(event awEvent, string contactName){
        actId = awEvent.Id;
        actLink ='View';
        actType = awEvent.Activity_Type__c;
        actSubType  = awEvent.Meeting_Type__c;
        actSubject = awEvent.Subject;
        actDueDate = String.ValueOf(awEvent.StartDateTime);
        actCompareDate = awEvent.StartDateTime;
        actAssigned = awEvent.Owner.Name;
        actFullDesc  = awEvent.Short_Description__c;
        actPrimaryContact = contactName;
        actOwner = awEvent.Owner.Name;
    }
}

Lightning Component:

<aura:component controller="ActivityFirmComponentControllerSCRewrite">
    <aura:handler name="init" value="{!this}" action="{!c.init}" />
    <aura:attribute name="actData" type="Object" access="GLOBAL" description="The page data"/>
    <aura:attribute name="actColumns" type="List" description="The data to be displayed in the grid."/>
    <aura:attribute name="parentId" type="String" description="The Firm Id to be passed to the query." />

    <div>
        <lightning:datatable data="{!v.actData}"
                             columns="{!v.actColumns}"
                             keyField="id"
                             hideCheckboxColumn="true"/>
    </div>
    
</aura:component>

Lightning Component Controller: 

({
    init: function(component, event, helper) {
      component.set('v.actColumns', [
        {label: 'DUE DATE',fieldName: 'actDueDate',type: 'dateTime'},
        {label: 'PRIMARY CONTACT',fieldName: 'actPrimaryContact',type: 'text'},
        {label: 'ACTIVITY TYPE',fieldName: 'actType',type: 'text'},
        {label: 'SUBTYPE',fieldName: 'actSubType',type: 'text'},
        {label: 'DESCRIPTION',fieldName: 'actFullDesc',type: 'text'},
        {label: 'SUBJECT',fieldName: 'actSubject',type: 'text'},
        {label: 'ASSIGNED TO',fieldName: 'actAssigned',type: 'text'},
        {label: 'VIEW',fieldName: 'actLink',type: 'text'}
      ]);
         
          
           helper.getAllActivities(component, event);
          }

})


Lightning Component Helper:

({
    getAllActivities : function(component, event) {
        var action = component.get("c.getAllActivities");
        var parentId = component.get("v.parentId");
        var returnJson;
        var returnValue;
        var state;
        action.setParams({
            parentId : '001m000000box8NAAQ'
        })
        action.setCallback(this, function(response){
            state = response.getState();
            console.log('state is '+state);
            console.log('action is '+action);
            if(state === 'SUCCESS'){
                returnJson = response.getReturnValue();
                console.log('***** response returnJson ' + returnJson.length);
                if (returnJson.length > 0) {
                    console.log('***** response returnJson actId is  ' + returnJson[0].actId);
                    console.log('***** response returnJson actDueDate is  ' + returnJson[0].actDueDate);
                    console.log('***** response returnJson actPrimaryContact is  ' + returnJson[0].actPrimaryContact);
                    console.log('***** response returnJson actType is  ' + returnJson[0].actType);
                    console.log('***** response returnJson actSubType is  ' + returnJson[0].actSubType);         
                    console.log('***** response returnJson actFullDesc is  ' + returnJson[0].actFullDesc);
                    console.log('***** response returnJson actSubject is  ' + returnJson[0].actSubject);
                    console.log('***** response returnJson actAssigned is  ' + returnJson[0].actAssigned);
                    console.log('***** response returnJson actLink is  ' + returnJson[0].actLink);                 
                    component.set("v.actColumns", returnJson);
                    console.log('***** after component set  ');
                } 
            }else if (state === 'ERROR'){
                var errors = response.getError();
                if (errors) {
                    if (errors[0] && errors[0].message) {
                        console.log("Error message: " +errors[0].message);
                    }
                } else {
                    console.log("Unknown error");
                }
            }else{
                console.log('Something went wrong, Please check with your admin');
            }
        });
        $A.enqueueAction(action);    
        
    }
})