How to Mass update the user license and profiles using batch apex for all the existing users 

There is a checkbox field in contact object named "Invalid email" as soon as it is checked. the active checkbox filed in USER needs to be unchecked. I am trying to create a trigger in contact but it is not working


trigger UpdateUserActivation on Contact (After update) {
    if(shouldIRun.canIRun() == false){
    CheckUserActivation.UserActivationUpdate(trigger.newMap.keySet());
    }
    /*string useremail ;
    //List<User> userrec = new List<User>();
    List<User> listofuser = new List<User>();
    for(Contact c: trigger.new){
        
    
    if(c.invalidemail == true){
        List<User> userrec = [Select id, email, isActive from user where contactId =c.id: ];
        if(userrec.size()>0){
            for(User u: userrec ){
                User usr = new User();
                usr.id = u.id;
                usr.isActive = false;
                listofuser.add(usr);
            }
            }
            update listofuser;
        }
    }  */  
}

There is a checkbox field in contact object named "Invalid email" as soon as it is checked. the active checkbox filed in USER needs to be unchecked. I am trying to create a trigger in contact but it is not working


trigger UpdateUserActivation on Contact (After update) {
    if(shouldIRun.canIRun() == false){
    CheckUserActivation.UserActivationUpdate(trigger.newMap.keySet());
    }
    /*string useremail ;
    //List<User> userrec = new List<User>();
    List<User> listofuser = new List<User>();
    for(Contact c: trigger.new){
        
    
    if(c.invalidemail == true){
        List<User> userrec = [Select id, email, isActive from user where contactId =c.id: ];
        if(userrec.size()>0){
            for(User u: userrec ){
                User usr = new User();
                usr.id = u.id;
                usr.isActive = false;
                listofuser.add(usr);
            }
            }
            update listofuser;
        }
    }  */  
}