If you turn it on & ring them up they will do the check there & then.
Then you should be free to turn it off.
They are also required to write to you before charging you for this.
Ring them up, get them to do the check then give you a refund.
If they refuse ask to be put through to "retentions" discuss this & suggest that your not happy & you wish to leave.
Chances are they will kiss your backside to keep you paying
Sky User is a good forum for sky problems.