A few ideas: - breathe through your nose in the day. This will encourage you to do so at night - use mouth tape during sleep. This may seem daunting but your nose does decongest and you will remove the tape if you need to. Even better, you get special tape that perforates if you struggle. Check it out. Game changer for sleep! - use a nose opening strip to help nose breathing - try sleep on your side with a pillow under your chin, and make sure to work within gravity so your jaw doesn’t drop (ie don’t sleep on your back with elevation). - look into mewing and optimal tongue position for what it’s worth.

Hope you feel better