Internet service poor

We are using Cell C via the Metro Fibre Network. The service is slow at times when needed. I have reported this twice to Cell C on their support @cfibre "Support, I have the following router installed,TG789vac v2, Techni Color Router. Address 7 Algoa Bay, Elandshaven, Alberton North

The reception is very poor and intermittent at times. Please investigate and support."

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