Sort yourselves out please

In the 2021 when I started my journey with Teljoy I did not have the tiniest bit of a problem, but in the last 6 months I have had a never-ending list of issues. I have tried to change my bank details with them multiple times but to no avail, so I just make EFT payments so that my account stays up to date now I am charged R18 "admin fee" because no one sorts out the bank details. At the beginning of the agreement, I got paid at the end of the month, so I paid at the end of the month, now I get paid on the 25th so I pay on the 25th but now all of sudden they "bill on the 1st" so by the 5th I get a SMS to say I am overdue after already paying on the 25th.