Do you mean you are trying to add another plan or feature because you cannot really change a feature on prepaid. Once you have bought a feature it's non refundable. If the plan is about to expire or you've used it all up, that is the typical time most clients pick a different plan if they were planning on changing their plans?
Hey @FishTire, this seems to be account specific, tech support will need to gather your info and look into this further. Best way is to use live chat and select technical support under Mobility. What they'll do is log a ticket and make sure it gets taken care of. Live chat is available on the contact page, option to chat will appear when accessed via a computer browser - http://www.telus.com/en/ab/support/contact-us?lang=en&prov=ab