Cannot cancel Club SMS on app and can't call a human. Can't wait on hold for 5 minutes!

I just want to scream. I keep getting sent your Club SMS. It says to cancel I must call your CS number but doesn't tell me what buttons to press. I click for a real human. Wait on hold with my precious airtime minutes for 5 minutes. The recordering keeps asking if I want to leave a message. I won't because no one will call me back then never do. After 5 mins I hang up. I have the app on my phone but there is no setting to turn off the Club SMS. WHY NOT????????????????????????????????? RIDICULOUS. I block the number sending me these infernal SMS but the number keeps changing!