Here's a mundane suggestion but are you sure you don't have just a big of a jagged tooth edge that you otherwise haven't noticed? That could be checked out by a dentist. It could be that you are inadvertently scraping your tongue against a teensy sharp edge of a tooth or teeth which causes the tongue sores.

Cheryl

Dogs love it when you leave your clothes on the floor


My guy If you can't be kind, at least have the decency to be vague. Author Unknown