Incorrect credit bureau reporting

This is the worst company iv ever had to deal with. Last week I submitted a complaint cause my account went into arrears as they didn't deduct on the correct date we had agreed apon but deducted a week later on the 7th mind you iv never missed a payment with these guys. Payment was made on the 15th so technically my account had been in arrears for 15 days. This morning I get my updated credit report and finchoice has reported the missed payment. The account being in arrears happened this month but on experian it now shows that I missed my march payment. I personally feel that them altering the date with the credit bureau could be as I submited a complaint here. The correct process was not followed an account is only delinquent if there was no payment made in 30 days and that's when you report it to the credit bureaus.