iPhone alarm playing faint

Background: received a new iPhone 13 back in July 2022 from apple care.

Problem: My iPhone "ringers and alerts" volume keeps lowering to about 20%, which caused me to be late to work twice now. I have it set too 100% volume and within a couple days it somehow ends up as low as 20%, I have no clue how it is doing this, but I need to fix this ASAP

Please read before I get the basic wrong protocol answer***********************

Change with buttons is OFF,

Reduce loud sounds is OFF,

Attention Aware features are OFF,