One angry customer

We own a small business. Our account goes through a renewal process in which we did not receive notification that it was time to renew. We received a bill for well over 4x the amount our monthly bill usually averages, I reached out to a representative. I spoke with this representative and was given a reference number, that was December 14th. I explained we would not make payment until this was corrected.  On the 28th of December our service was interrupted at which time I reached out to another representative. Some action was taken at that point, adjustments made but still had to make a large payment that was Accumulative to 2 months of average service for our business and our account was supposed to have a safeguard put in place until this was resolved. Again, our most recent statement is showing monthly charges of almost 900.00 and showing a past due amount on the account.....We received another service interruption notice and cannot get through to speak to anyone unless another payment is made. I am furious! At this point I am seriously considering filing a complaint with the FCC, don't know what assistance they may be able to provide but it's got to be better than this! I have spent hours on the phone and become increasingly frustrated, I need results. Any assistance would be very appreciated.