Why might I owe additional money on a plan that has been canceled due to pet death or another reason?

Yourgi Bestlife breaks the average yearly cost of pet care into 12 payments, which allows you to redeem services when your pet needs most during the annual plan. This means that if the value of services redeemed is higher than the amount of membership dues paid-in, additional payments will be owed for the cost of the services redeemed prior to the cancelation request.  

If an outstanding balance is owed, the member is to pay X additional month dues to cover only the cost of services received, not to exceed the total membership plan cost. (Total plan cost is equal to 12 monthly subscription fees for selected plan, subject to local taxes)