My device is no longer charging via transformer

My ring doorbell 2(bought second hand) has recently stopped recognising as being hardwired so I have to charge the battery every few weeks.

the transformer is rated at 24v AC 3A(72vA) and I am still reading 24v AC at the terminations when powered up so the transformer is working as expected.

I can only assume something has gone wrong internally but obviously the device is outside of any warranty so it’ll be down to me to fix or repair.

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Hey I’m having similar issues but mine charges intermittently. It also causes my doorbell to hang and hum and give off a burning plastic smell. Hopefully you’ve figured it out.

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