Worst Service Ever

To my bank: I use HomeCloud as a service provider for internet at my home. I have been with them for almost 5 years, so am not under a contract but month-to-month. I have disputed debit orders in the past, because they hardly ever load the correct amount of data. I have emails dating back as far as 2017 where I disputed data issues and have also in the past requested FNB to dispute debit orders. HomeCloud eventually always fixed it, but at my expense. I requested to close my account in July. They require a 30 day cancellation period, so I assumed it would be closed end of Sept. This month, I did not receive data on the 1st, which is when contractually, Im supposed to receive data. I was very relieved, because one of my colleagues attempted for 6 months now to cancel her contract, without any results. The issue as well is that I have no evidence of giving notice, because the process takes place online and they do not send you any confirmation messages. I sent them emails to request so (in July), but they just referred me online. I completed the online process, knowing that they will just deny doing so. Today, again, I tried to create an online profile so I can monitor my account (this is a new facility). Yet, after creating the online account, I cant access it, because I need to verify my account, which I cant do, because no verification email as is explained, is sent to my email address. To begin with, my original contract with them states that I have unlimited night data. After two months, the night data was removed without any notification. When I eventually managed to get hold of them, they informed me that the special has expired, so they will refund me R70 a month. This, to begin with, is a breach of contract. How do I resolve this? For as long as they load data, I will be obliged to pay the debit order, which is what they abuse at this moment. I can get much cheaper data almost anywhere right now. In addition, I work from home. This month, my data was loaded on the 5th or 6th. What if my income depended on having data on the 1st? In addition, I was only given part of my data. If you go to Hellopeter and read feedback on the company (Review Companies Online | Customer Service & Company Ratings | hellopeter.com), you will see that they have a trust index of 1.6/10 out of 420 reviews. Please advise.