Hi current
Make sure you are on latest software version which is .122 if not, you can check by
Go to setting => System => About => Software information.
If you have already updated please share the overall SOT of your phone:
SOT(Screen on Time) can you share the SOT after trying the below:
1. Charge the battery to 100% & use as per your normal usage pattern
2. When the battery strength reaches 10%, go to settings = Battery => Tap on the battery icon & share the graph
3. settings => Battery => Check the screen & share the same