First Alert ZCombo not pairing on my ZWAVE on Ring alarm station

1st off all, it took me a while to figure it out and although they are brand new, my 2 new ZCombo smoke/CO detectors are FIRST Generation. I followed all instructions to the letter to reset them (press test button while inserting batteries), help for 3, 10 and even 1 minute to no avail. everytime I try to add one, it recognizes the QR code that I scan but keeps telling me my device needs a HARD RESET. The Help file says to push a pin in the hole in the back of the unit but I don’t have a hole on these (maybe it’s for 2nd generation). After spending 2 hours on these, I am ready to give up. any suggestions out there please? thanks