Telkom worst Internet SA

I've had a contract with Telkom 2.5 Y. I've written multi pal complaints to them and had more than one "Chat to a Agent" chats. I've always received the same response : Sorry ou technicians are looking into it ( 5 days later) Chats to agent : Do the following:Please see below

please switch off your device, remove the sim card, switch it on without the sim card, wait for 2 to 3 minutes while it is showing the red light, switch it off again and insert the sim card and try to connect again.

Always the same trouble and no one could explain to me why after 8 PM my internet goes from PAID 4.5G to 4-3G and my internet speed goes from 20ms to 550ms

I can't take this anymore. THERE services is PATHETIC. My internet was so bad that I couldn't even apply for cancellation of contract at my house I needed to do it from work. Following up on it the following day they told me they will only start processing it in 21 working days *** ??