Chime 2nd generation suddenly stopped working - any tips?

HiI have a chime 2nd edition - that I’ve had for 3 years - working since April XXXX. In January this year it suddenly stopped working.I’ve followed the troubleshooting guide - but the device isn’t behaving like how the guide says it should.I can’t get the green light to flash.If I press the side button for 5 seconds - the green light turns off after 3 seconds, and then a few seconds later comes back on solid green. No flashing.If I press the side button for 20 seconds - after XXXX seconds the green light comes back on, after a further 30 seconds it will flash once or twice, and then go back to a solid green.I clicked on the troubleshooting guide in the ring app - and it said “Oops…that doesn’t go anywhere yet”.Can anyone give me any tips?