Vodacom - Poor signal, Poor Service

I have called and emailed Vodacom on numerous occasions due to the exceptionally poor reception I have been receiving at my office in the past few weeks. I have logged complaints, had network synchronizations reset, sim card swapped and spoken to people in Customer Care and Network, all to no avail. I have been told that there is congestion on the network and they are unable to tell me when the problem will be resolved. I have merely been advised to purchase a signal booster which may work, but probably won't, given that it feeds off the already congested network. So for the past 4 weeks I continue to miss calls from customers, return calls at my own cost, yet pay Vodacom 100% of my bill. I am beyond frustrated and angry at the lack or service and "there's nothing we can do about it" attitude. Under the current circumstances I think it's shocking that a company can provide 30% service and expect customers to pay 100% plus, to try and improve THEIR poor service.