I cannot validate my exercise: create a data model using clicks

The validation is running for House Field, not for House Name. That's why validation getting failed to fix the validation just needs to be copied House Name into House field that's showing now auto generated salesforce Id.

You can use below SOQL to copy the House Name into House field

List<House__c> houses = [Select Ids__c, House_Name__c, Name from House__c];

for(House__c h : houses){

    h.Ids__c = h.Name;

    h.Name = h.House_Name__c;

 }

update houses;

Note : I've created custom Id field to store auto generated salesforce Id. You can also or just remove the  h.Ids__c = h.Name; line from above apex code.

Thanks

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