TNT Sports was included in the Bigger Bundle + Sports and the Ultimate Oomph and Ultimate Volt bundles as part of the package.
VM changed their packages on Monday 1st September and from that date any new customers signing up to VM will have to pay an additional fee of £18 per month for TNT Sports as it's a now a premium add on and no longer included in any bundles.
The Bigger Bundle + Sports is now the Bigger Combo Bundle + Sports HD and only includes the Sky Sports, Eurosport HD, and Viaplay Xtra sports channels.
The Ultimate Oomph and Ultimate Volt bundles are now obsolete and have been replaced with the Mega bundle.
Any current customers negotiating a new price at the end of their minimum term, or changing package will also have to pay an additional £18 a month if they want TNT Sports.
If you don't need the recording facility of the 360 box then in might be an idea to ask about switching to the IP based Stream box. You can add TNT Sports to that box for an additional £10 a month, however it's currently restricted to one box per household and can only be taken with VM broadband.