Poor internet speed since Cell C had a network issue this weekend

Good day. Since this weekend when Cell C had the internet connection issue my internet speed decreased significantly. This whole week the internet speed is so slow I cannot do anything via the 3G/LTE package that I have. Prior to this week I never had any problems to stream or browse on the internet. Please assist. The data SIM I use is linked to the following number: ********** . My address is 127 Friedman Street, Vanderbijlpark. I did reboot countless times and tried 2 different routers. Same result. No increase/change in internet speed.