Absolute Terrible service & customer treatment

I bought myself a month to month SIM Card with Rain which I then cancelled the end of April because we switched over to Fibre, I informed their Customer Service that I wont be needing any coverage going forward & I got a ref number (***) stating that it is cancelled. I then needed to use the Sim in July so I paid & didn't receive any coverage, I logged a call for that & was told I will be refunded, I am still not refunded & now I am being told I was in arrears for June so they took that money, please someone needs to explain how I can be in arrears on a month to month terrif & also how I can be charged for services I never received.

I seriously cannot believe it takes a whole month for a query to be resolved.

Regards,