I subscribed to a MONTHLY TRIAL yet when i go to cancel it says i have to pay an outstanding $90 annual fee. why do i have to pay a fee.
For all help with accounts and billing you need to contact Adobe Customer Support.
Go here and use the chat bubble ("Contact Us") at the bottom right of the page:
This is a user-to-user community forum and people here will not be able to help you with this. Also, your question is probably not about Adobe RoboHelp but some other Adobe Product, so the Adobe RoboHelp technical support that Amebr recommended is not the right contact.
Please have a look at this page: Account and membership help
Especially here: Cancel Adobe trial or subscription