Bill not including Discounts?

After reviewing my bill, I noticed that they were not applying the discounts that were to be deducted from my service amount. I called in 3 times over the weekend and did not get an answer. To avoid disconnection, I paid about half of what was due. Have been trying to resolve this over the weekend but haven't been successful in getting in touch with a representative.  Has anyone else had any issues like this and what should I do?