Yext has the internal control to global opt-out an agent or advisor's contact conversation list. However, this will opt-out every conversation contact and cannot be done on a case-by-case basis.
By default, deactivated Relate numbers are held within Relate and are unaccessible to users. However, if requested, Yext can reinstall the un-used numbers back into the system for future users to utilize. No conversations or contacts from the prior account owner will be preserved or carried over.
Contact Support at support@hearsaysystems.com for assistance.