Cancellation of contract

I am assisting a client, who has signed a Power of Attorney with me. He wishes to cancel his Virgin Active membership as he cannot afford to continue paying. When contacting the Victory Park branch I am informed that he has 6 months remaining on his contract and that he is liable for 40%. Fair enough. However I must contact Virgin Active call centre tel. no. *** to cancel. The problem is that I had already called this number on six separate occasions and held on for over 5 minutes each time without getting a response beyond the frustrating message \please hold for the next available agent