Exercise options: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9550520/. Swallow while doing bridge exercises.

There is a device available in Europe, but not in the US, for exercises: https://www.iqoro.com/. I am experimenting doing the Iqoro exercise with a cheap mouthguard with a strap. Here is an example: https://www.amazon.com/Oral-Mart-Black-Strapped-Youth/dp/B0B3G4LR52/ref=sr_1_6

Good luck!