Yes, thats why p30 pro has a better battery. It kills in the background even though you optimize the battery to not close it. The other option is to find the app, and cannot recall now since i don't have this hyped phone anymore, but somewhere in the settings - Apps - Ring, select it to launch manually (it would be set to automatic). Doing this will give you notifications 95% of the time. The other option is to remove "power genie" app using ADB(google it for Mate 20 pro) and that might work, but you will loose the battery consumption stats. Sorry, cannot help much here without the device.