Incorrect billing and Poor Customer Service

I have taken an fiber with MyOwnISP with 3 months discount.

When invoiced - they send the invoice with the original amount. I am not threatened that they will cut my internet while they have acknowledged that it is their own mistake and they will rectify it. To this day, I have been following up everyday with their call centre agents saying it will be sorted out and it is never is sorted - poor service at its best