HELP - adding monthly plan for additional cameras wiped away my paid annual plan for my doorbell!

My front door was on an annual plan ($30/year) and that was good until January 2021. I added two more cameras and put those two cameras on a monthly plan so I can get them all under the same plan in January 2021... but it caused my front door to change to monthly! It completely overwrite my annual plan that I already paid for. How do I get that reverted?