Hello JenLi,
When did you get your pre-paid line? Unfortunately, Fido no longer offers their By the minute plan, some customers may have that plan grandfathered-in. That plan would have operated like the more traditional pay-per-use model. The current pre-paid offerings require the monthly or daily plans (see here). With these plans, you would need to pay the monthly or daily plan fee regardless of whether you actually use the services or not. For the fee, you are allotted a certain amount of services (depending on plan). If there are sufficient funds in your account, the fee will be taken for the plan costs. If your account does not have sufficient funds to pay the plan fee for the following period at the end of any given period, a 35 ¢/min rate will apply to the $10, $15.75 and $25.75 plans; a 40 ¢/min rate for local calls will apply to the $1, $30, $35, $45, $55, $60 and $70 plans (taken from Full Details in above link).
Without knowing your actual plan details or the balance on your account prior to your refill, it's not possible to calculate why your remaining balance is the amount you quoted. However, it's possible that your account did not have sufficient funds for a full monthly (or daily) plan fee prior to your refill. However, once you refilled, your account did have the required funds for the monthly (or daily) plan fee and that amount was taken for access to your next cycle.
Hope this helps 😀
Cheers
