No help with allocating payment

I have made a payment on the 03.06.2018 to my account, on the 21.06.2018 I received a green letter, I went to see them on the 23.06.2018 with the proof of payment asking them to please allocate my payment, 25.06.2018 correspondence was sent through with the proof of payment, 28.06.2018 electricity was switched off, 29.06.2018 went to see them again with the email correspondence and the payment, again they said they will allocate the payment, and requested the electricity gets reconnected. On the 11.07.2018 we received a sms that the electricity is in arrears and we have one day to do the payment or further steps will be taken, again I sent an email with the proof of payment, 12.07.2018 went to the office again with all documentation, lady at general queries said it will be allocated. Today is the 17.07.2018, I received another green letter. When will this stop, how many times must the proof of payment be sent through and made copies of before payment gets allocated.