It kinda depends. The official rule is that if you should have been able to do it online, but could not because of a system problem, then you should not be charged.

But if you just chose to use the phone instead of trying to do it online, or if the option to upgrade online has never been designed to work, the offline fee should be charged. However, people sometimes get this waived if they can convince the agent its a system problem.

So, in your case, it depends if you tried to do it online first, and if so, and it failed, should it have worked.