I am not able to receive any gmail notification, no matter what. I've already tried turning off power optimization, power saver mode, turned on all notification from within the gmail app also had turned all the notification from notification settings. Even tried and rreset my device to factory settings. Still I am unable to get Gmail notifications. The only notification from gmail that I get is "syncing mail". Due to this, I've already miss alot of important mails.
I am also facing this issue since last few days. Did most of things as you have except factory reset. I believe this issue started with Gmail app update which came with Google Meet tab. I think there is no solution rather than to wait for Gmail app update OR use different email client app.
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