Data locate

I took out a router with Telkom mondo on contract for the first 2/3 months things were OK. I'm suppose to get 10gig monthly but I don't think I'm getting it, right now the route is showing that I have 7 gig but when I check my balance its saying 5,7 gig but still its telling me that I'm out of data. I can stop at anytime to pay them and start buying data manually they must not try me. Come time to pay I don't give them any problem so they must not give me any problems when they suppose to locate 10 gig for me I'm not happy with they service at all I regret taking out the route ref no ( ***)