They’ll claim you’re in arrears even when you paid them

Got a loan with them and my first installment was the 1st but they deducted earlier then came back again and deducted on the 3rd of Jan I called and was refunded now it keeps saying I’m in arrears and getting calls from debt collectors when my account isn’t in any arrears talked to a consultant by the name Caitlyn who said they have an issue so I must ignore all of those things and yet they’re affect my credit score and I’m getting 6+ calls everyday from these collectors for an account I don’t owe with no communication from Wonga regarding whatever “error” said that they’re experiencing so unprofessional.