Flow Error "Looks like you don't have access to this field, or the object or field API name is not valid on this Lookup component."

Hi, I am having issues with Lookup fields in a Screen Flow.  I want to populate the default value for a record a User picks.  It works for non lookup fields, ie Text, Currency and Date fields.  I am having issues with Lookup.

I assume I can put whatever for "API Name" and "Label."

I assume Object API Name is our custom object Deal__c.

Here are the Field API Names I have tried.

{!GetDealRecord.Advertiser__r.Id}

{!GetDealRecord.Advertiser__r.Name}

I get error "Looks like you don't have access to this field, or the object or field API name is not valid on this Lookup component. Contact your Salesforce admin for help."

Thanks!