Can't remove battery from Ring Video Doorbell 3.

I can't remove the battery from a Ring Video Doorbell 3 which was recently bought just a few days ago. I've watched the appropriate videos and the method looks simple enough, but when pressing the 'PUSH' tab and simultaneously pulling downwards on both sides of the battery - the battery simply refuses to budge. I'm guessing that the 'PUSH' tab isn't correctly releasing a lock on the battery (but that's just a guess). The battery is now almost flat. [Update]. I've just contacted Customer Services who suggested that I unscrew and remove the doorbell from the wall and see then if the battery will come out. I've done just that and now the battery has been removed and is currenly being charged. Once it's fully charged, I'll re-insert the charged battery and repeat the process of removing it again. If the same problem persists again - then it will be another call to Customer Service, because obviously it shouldn't be necessary to physically remove the unit altogether from the wall every time the battery needs charging. I wonder if other people have had the same issue ?.