My store is paused around September,2019 before the 14-day trial expiry and recently got charged $9 for past two billing cycles
Do refer the attached screenshot
Based on the context, you would have selected the “Full Pause” plan which allows store owners to pause their store for up to three months free of charge. Once the three months have passed or the store is reactivated (whichever comes first) the account will begin billing you on the “Pause and Build” plan which is $9/month.
The amounts can not be refunded; however, you can choose to fully close your store if you wish to cancel all future billing. Alternatively, you could select a paid plan, then move back to the Full Pause plan if you wish to pause your store for another 3 months.