Allow a single record associated to a single CRM Contact

Allow a single record associated to a single CRM Contact

Hello.

I'm building a form which I need to restrict to create only a single record for each CRM contact.

Once I add the Integration field on the form. It loads all Contacts but I need to have available those contacts that doesn't have a record created yet. And add a restriction to create more than one record for a single contact.

I still haven't found a way to do this.

Any help is appreciated.

Thanks