Honestly, if the Battery drain has went on for more than just a day...You might want to check the Device Care app and see what is using the most power. If you can't find an obvious cause after doing some basic troubleshooting, then a Factory Reset might be in order.
Google Maps was draining an absurd amount of power after I updated my Note 8. However, I put the app to sleep and since then my battery life has improved quite a bit (included screenshots). There's always an app or two that might behave oddly after such a major update, Device Care is a helpful tool for finding the offending app.
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