Someone has hacked my phone sone how and I can’t figure out how

sounds more like you have some compromised accounts.

see if there are unexpected devices using your Apple ID

Check your Apple ID device list to see where you're signed in - Apple Support

change your Apple ID password

Change your Apple ID password - Apple Support

review this too

If you think your Apple ID has been compromised - Apple Support

When you say 'messenger'.. if you are referring to Facebook messenger, that's a different issue, you'd need to change your Facebook credentials.

make sure not to share your credentials with other people. Make sure the passwords are strong.

Don't share an Apple ID. If you are not using a passcode on your phone, use one and don't share it with anyone. Turn on two factor authentication if it's not turned on.

That is virtually impossible.

What makes you think you've been hacked?