Pathetic service

My LTE Wifi has been unworkable for the last 5 months, I have had the router changed with Telkom, still no issue, the problem is , in the morning the speed is OK, in the afternoon and evening I don't even get 1MB download using ping test, I'm in IT myself, the tower is congested I have called Telkom 3 times, logged complaints, the last women I spoke to says oh sorry sir sounds like the tower is congested, so basically in a nutshell they have told me live with it, I will not pay for something that was working and has now stopped due to Telkoms infrastructure not being able to supply the demand, this is the second time im posting this, I WANT MY CONTRACT CANCELLED, im sick of hearing its been escalated and someone will come out to have a look. your service is shocking,