Horrible customer service

I've been with old Mutual for a while and I'm very disappointed and fed up with their service I've complained several times about not being able to use my rewards points it keeps on saying global error for the last 3months I'm earning points that are useless that I can't even use I wouldn't recommend it to anyone. I've complained so many times but non of them was willing to help they keep on saying they will get back to me. Since last year no feedback