Hello YouKnowWho,
Welcome to the community!
Sorry to hear your plan cost increased unexpectedly. Generally, Fido informs customers of account related information (ie plan cost increases) on your bill. They would normally notify customers a couple of months prior to the actual increase.
I understand you may have been told that there was no expiry date. While some promotional or win-back (retention) plans may include discounts or credits for a specified period of time, an expired promotion does not sound like the reason for your price increase.
I also understand people like the notion that prices would never increase. Unfortunately, however, the cost of everything increases. At some point, those added costs would eventually increase the operating costs for companies. I don't think it's feasible for any business to not occasionally adjust their service/plan prices in response to rising operating costs. So the price increase you note was a general price increase on certain plans (see here and here). Those price increases are not generally not foreseeable so customer service at the time would not have been aware of the increase.
Unfortunately, since the increase appears to have been applied to other plans as well, I don't think there is any way to remove the increase. That said, you should note these forums are community-driven and not intended as a venue for customer services. If you would like to discuss your matter, you would need to contact customer service again for assistance. 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 😀
Cheers
