BillionGraves website:

#1 Log in to BillionGraves.

#2 Hover over BG Plus Tab (main menu).

#3 Click Manage Subscription button 

#4 Click Cancel Subscription.

OR

#1 Log in to BillionGraves

#2 Hover over Research

#3 Click other tools

#4 Click BillionGraves Plus

#5 Click Manage Subscription

#6 Click Cancel Subscription


* Please note this only stops the auto-renewal. You still have the service paid for.