I have successfully created the wave dev account multiple times, but the check button on the trailhead still does not recognize the newly created account.  

I have successfully created the wave dev account multiple times, but the check button on the trailhead still does not recognize the newly created account.  

I am facing the problem with the above trailhead unit and the error is 
The component is missing the 'aura:iteration' component and my code is:
MycontactList.cmp
<aura:component controller = "MyContactListController" implements="flexipage:availableForRecordHome,force:hasRecordId" access="global" >
    <aura:attribute name="recordId" type="Id" />
<aura:attribute name="Account" type="Account" />
<aura:attribute name="Contacts" type="Contact" />
<aura:attribute name="Columns" type="List" />
<aura:handler name="init" value="{!this}" action="{!c.myAction}" />
<force:recordData aura:id="accountRecord"
                  recordId="{!v.recordId}"
                  targetFields="{!v.Account}"
                  layoutType="FULL"
                  />
<lightning:card iconName="standard:contact" title="{! 'Contact List for ' + v.Account.Name}">
    <!-- Contact list goes here -->
    <lightning:datatable data="{! v.Contacts }" columns="{! v.Columns }" keyField="Id" hideCheckboxColumn="true"/>
</lightning:card>
</aura:component>

 

I have successfully created the wave dev account multiple times, but the check button on the trailhead still does not recognize the newly created account.  

Running into a strange issue -- I have developed several lightning components that are displayed in Lightning App Builder. I added a second one that has all the same "implements=" as the other ones, but for some reason is not showing as an option in App Builder. Given the fact that other components are showing up - any ideas/thoughts on things to check? Here is my aura:component line:
 

<aura:component controller="SecureSiteController" implements="force:appHostable,flexipage:availableForAllPageTypes,flexipage:availableForRecordHome,force:hasRecordId,forceCommunity:availableForAllPageTypes" access="global">