Settlement letter

The worst experience, I've paid the my account on the 21st of January and sent a proof of payment on 23rd of Jan, I called on Monday they said they will log a call because the reference on my pop is not correct, and the issue will be sorted in 48 hours, i called on Tuesday to check the status on my log, apparently they cannot find anything today is Thursday still the same answer, this is the worst service even the costumer reps are rude and they are not professional, I'm so annoyed