Paying for nothing - I was denied access but expected to pay

I have been a member of Virgin Active for years and have been paying them until end of November since I lost my job. They did not cancel my membership but stopped me from entering Virgin Active to train. And now they demand me to pay R1664.80. They have even escalated my account to some lawyers. They embarrass me calling me more than 3 times a day. I have explained to them that I'm not working but they said their calls are automated. I'm now working and thinking I should just pay them and cut my relationship with them