Is it normal to sleep with your tongue on the roof of your mouth?
Yep.Totally normal
Yes, it’s normal for your tongue to rest against the roof of your mouth while you sleep. Your tongue’s position can shift during the night, too.
Lots of people naturally rest their tongue against the roof of their mouth, including while asleep. It’s a comfortable resting position for many, and you usually don’t need to think about it or try to hold it there.
Your tongue may move around as you change positions or pass through different stages of sleep, so there’s no one position it has to stay in all night.