have any of you used a tmj guard or some sort of mandible guard

[Phad]

I got my tmj guard today which is suppose to fix my bite and bring my MANDIBLE FORWARD. I was so excited but when I tried it on my maxilla completely vanished and my face is flat and gives me resting bitch face while making me look autistic.

Will my maxilla move along with my mandible or is this guard a bad idea?

 

[Nibba]

mewing will fix both issues tbh. go on ali express and get myobrace instead