Razer phone battery problem

Can anyone help me. I have a razer phone (the first one) and after updating to the latest Android (8.1.0), I have been facing some battery problem in my phone. For some reason the phone always constantly keep using up my battery, even when I'm not doing anything and takes even more charge when I'm using the phone. The phone often heats up as the system is always running in the background and may deteriorate the battery even more. I already tried many battery saver apps and the battery saving mode, but it doesn't work. I have thought that Android 9 may fix the problems on my phone, but no one has yet announced Android 9 for the razer phone 1, unlike razer phone 2. So if anyone knows about when Android 9 would be released for razer phone 1 or if anyone knows how to solve this battery problem, please let me know. Thank you.

 

Update:
I just went into developer options and turned off background processes completely and also turned off the background process of Android system, and poof the battery problem is solved, so if u thought it was a hardware problem then u r wrong. But I don't like this solution since I now have to turn off the background process in developer options everyday. So if anyone knows anything about when Android 9 is coming to razer phone 1 then please tell me, cause I feel like that would be a more permanent solution to my problem. Thank you.

 

When did the problem begin ? Did reset to factory firmware? I after the acquisition of moved with “3” (CKH) on global . In standby mode up to 10 days, with active use of 2 days. I advise You to reset to factory !!! If not will help you then reflash

8.1 works fine

 

By my experience I don't think android 8.1 is battery friendly for my phone and I think it got even worse after factory reset. Cause before the reset I was able to stop the battery problem by turning off background activity of android system in developer mode. But ever since I factory resetted the phone that option for some reason suddenly disappeared. The background activity option in developer mode now doesn't show the option for android system and also many other apps that it showed before. This is some celestial level unluck that I'm facing. If you know anything about how can I fix this then please let me know. I would be very greatful. Thank you.