iPhone 12 Pro Max Alarm Volume adjust on its own

I am competent on how to use my phone. I know how to adjust the volume buttons in settings and my side bottoms are set to volume adjustment. Why when I turn the volume up for my alarm clock does it not ring loud to my adjustment ? There is no issue with my phone no malfunction. I had a diagnostic run on my phone at Apple Store to detect any issues. All apps are up to date. I keep my phones properly updated. Stop the customer shift blaming for poor quality. There is no excuse for my alarm clock volume to self adjust. APPLE KEEP THE QUALITY OF YOUR PRODUCTS (even if it’s not the latest and newest model). If this keeps happening I am considering not buying APPLE PRODUCTS. My backlighting adjust on its own as well. I have watched the display brightness bar adjust on its own many times. If this a push for me to buy a new phone it’s NOT WORKING. You will push me away from Apple for good. STOP MESSING WITH MY PHONE. PLEASE AND THANK YOU .