Vodacom always have excuses

I'm so ****** disappointed in Vodacom, my blood is boiling with anger. I have 2 contracts with them, 1 is my number the other ones sim i use in a router. Both get airtime each month. Last week i discovered on my vodacom application that all my airtime disappeared after I used my router (I bought data with some of the airtime). So when i called now to ask what was going on they said it was out of bundle rate but for all the time i had this no. I never had this problem (plus there are some subscriptions on the number) how the f can I subscribe to something if i don't use the cell number in a phone???) they are refusing to refund my airtime after I suspect them of changing my out of bundle limit.