Furthermore, nearly every campus and ISD prohibits phone use during class in their student conduct codes unless it's for academic purposes - meaning, at teacher direction. Some even expressly prohibit phones being on or out at school functions.
If admin isn't going to support you; if they're going to bow down to the parents, that's when you file a grievance and air up the tires. You're being prevented from following campus and district policy. That's a grievance that is quick to handle, even if it's not going to end well for you - but your behind will be covered.
In short - follow policy and document every time an admin asks you to ignore it. "Per our conversation on (date) at (time) in (location), I did (action) by your direction." Email the admin and bcc a personal email address. Fecal matter rolls downhill. Make sure it doesn't stick to you.