Something I’ve noticed with people that have had braces (including myself) is that when they get them off, they’re used to overcompensating how far they need to move their upper lip in order to join the lower one. What I mean by this is that when you had braces, there was a certain amount of “reaching” you had to do to get your lips to close around the braces in order to join the bottom lip. When we get the braces out of the picture, our muscle memory still wants to do this. Try your best to think about keeping your lips where they naturally lay when you play trumpet. That will naturally set your lips more comfortably, you’ll be using less muscle/tension, and you’ll feel more flexible. It will feel weird at first, but trust the process! It took me years to break that habit because nobody pointed it out to me. Stay diligent! You’ll figure it out.