@(you need an account to see links)
@(you need an account to see links) had this same problem not too long ago.
I don't think it was ever resolved - it was for Premium she'd purchased for a friend, so she didn't want to ice their account for her to get her money back, but TNT was (of course) super unhelpful.
I think the only options are to sacrifice up the account for the full year or just suck it up and take the hit of being charged with Premium.
Because why on earth would TNT consider the fact that they could just have good customer service for once?
Sorry about the problem you're having.
Maybe someone else has gotten better luck, but I don't believe it ever worked out for Colbs - hopefully someone has some better advice, though!