Various requests and no response

I upgraded 3 contracts at Tyger Valley in the beginning of the year.As the 3 cell numbers were on 2 different account names I requested to have all 3 transferred onto the same/new account. I had to go into the store 4 times before this was done.Obviously payments for the 3 cell numbers went through every month as usual but when the numbers were transferred to the new account a credit balance was left on the initial accounts and the full amount was charged to the new account .Since August I have received sms's threatening to suspend my account if the full amount on the new account was not settled.I made a summary of everything explaining that if the credits were transferred to the new account,it would in fact all be sorted out.I have spoken and emailed 7 different people and have also spoken to a supervisor explaining the whole concept over and over again.It seems as if these consultants understand when I speak to them but on Friday I received another sms regarding suspension of my service.I once again phoned and explained and the consultant promised that she would sort it out.This evening my service has once again (for the third time now) been suspended.Where to next?