Whenever I left Thailand on my retirement visa, a reentry permit was required. Fail to do that and your retirement visa ended when you left the country no matter what the normal expiration date was. Never heard of a retirement visa with multiple entries, but if that is what is stamped in your passport them reentry permit should not be an issue.

@Tod ********

the foreigner does not "do" the TM-30.

Never been asked for a TM-30 in the past ten years. TM-30 is the responsibility of the homeowner/hotel. You should never even see it, let alone have a copy of it.