Disable old contacts

Disable old contacts

Hi :)

I would like to mark old contacts as obsolete that are no longer employed by the corresponding company or similar. It is not spam and I do not want to delete the contacts/tickets as they might contain valuable information. I don't want users to be able to select these contacts when creating tickets, but existing tickets should remain associated with the contact.

Do you guys have any ideas on how I could make this work?

Regards,
Sven