HELP PLEASE!!!

I have the ring door bell 2nd generation and my door bell is non responsive, I’ve tried the orange button and I’m not getting anything from it, I’ve had it on charge for 48 hours and it says it on 61% ive used 2 different chargers. It says to hard reset you need to find a black button. I’ve taken the silver case off the bottom but can’t seem to locate the black reset button. Can someone please tell me where this is? Thank you