No response to lost service for 4 months

We have tried for 4 months to have someone come out and look at our internet. We have waited on hold an average of an hour to be told that the problem is on our end. We have spent over 500 dollars fixing all the things that we were told to take care of. Still nothing worked. We have tried for the past month to get someone to come out and since we pay a maintenance fee, which states the problems will be taken care in a matter of 48 hours, still nothing. We did receive word today that the problem will be corrected sometime the next month. This is a business account and I do not know how much money we have lost. I do know of over 1000.00 and this does not include the monthly fees.