Welcome to the community!
There used to be a promotion whereby you could use some of that balance to extend the expiry date. Unfortunately, I believe that promotion has already ended (see here).
As you are aware, the top-up values have a set expiry date (see here). The only top-up value with an expiry of 365 days is the $100 denomination. You should note the expiries are not additive. For example, with the $100 top-up value, that expiry is 365 days -- from date of purchase. If you topped-up $100 today and again next week, the expiry date for the total value would still be 365 days from the last top-up date. It would not be 358 + 365 for a total 723 days.
If you topped-up today, you account balance would expire in 365 days, not 365 days + 2 weeks (approximately).
You should note that Fido had put a cap on the pre-paid balances (see here), though I'm not sure if that measure is currently in effect or not.
Your best option would be to discuss the matter with customer service. Alternatively, you might consider sending @FidoSolutions a PM. Once they verify some information, they will also be able to access your account. In addition, they can also be contacted via Live Chat, Facebook, or Twitter. Those methods can be accessed via the contact page posted above.
Hope this helps 😀