Missing Ring Protect Plus Trial

Hello. I purchased my Ring doorbell with a one month trial of Ring Protect Plus. I purchased the Ring Home Security system from Costco which came with one year of Ring Protect Plus. The one month trial has now expired and the Ring app has indicated my system is not being monitored. I understood the one year trial would automatically commence after the one month trial, but it has not. Please confirm how to activate my remaining one year of Ring Protect Plus provided through my Costco purchase.