Over billing and disconnection

I really enjoyed the rain network as it is unlimited and they never gave me a problem, Up until I requested a new rooter which was delivered on the 4th of December 2023 and I reported on the 5th that they should cancel the old one as I was then connected to the new rooter. They never canceled and on the 26th January 2024 I was disconnected and when I asked, they told me of the outstanding balance of which was higher than expected and I was told about the new and the old rooter balance, I told them that I cancelled the old rooter and they told me that it was never canceled but their system shows that I called for cancelation on the 5th December 2023. Meaning someone is not doing their job on their side. I paid for the new rooter and it was immediately reconnect on that 26th January 2024. On the 2nd of February 2024 it was switched off again and when I called they said the matter has been escalated as I was told on the 26th of January 2024. How can the matter be escalated for 10 days or more? Then the network was connected for 1h30 min, then switched off again. I called them more than enough times telling them of the same story and they told me the same story of escalating the matter. I haven't worked on Saturday the 3rd January 2024, then I bought prepaid data so that I don't loose the Sunday, and I again called and they said the matter has been escalated. This is not fair, I was warned by a lot of people not to use rain network as they rob people and I never believed them as I never encountered any problems before now. I am tired of making calls to them, they are a no go service provider. I am tired of rain. I am soo disappointed, sad and hurt for loosing a working day because of rain.