My Zenfone Max 2's ringing volume is automatically reducing. I tried to increase it, but it is again and again reducing automatically. How to fix it
Have you checked whether the volume buttons are stuck?
If it is not the volume key stuck causing, I would suggest enter the safe mode to confirm whether the situation still exists.
If the situation remains the same, please try the following steps to access recovery mode for the Factory Reset:
0. Try to back up your data with USB cable. If you can not access the phone, please check if your google account or microSD card have auto backup your data.
1. Power off the phone, then keep pressing "volume down key"
2. Press "power key" and stop press " power key" once you feel the vibration. Still keep pressing "volume down key"
3. Stop press "volume down key" once you enter [Android Recovery] Screen
4. Choose "Wipe data/factory reset">"Factory data reset"
5. "Reboot system now"
#Hardware Reset Guide
Please note that once the steps are completed, all data, apps, settings and personal information will be deleted.