Error that will cost me my job

I have a loan at capitec.my loan is been paid via debit order and went through on the 31 March 20.On 31 March 20 I was listed on tpn for 1 month in arrears and was declined a homeloan because of this.*********** people.i even emailed customer services and didn't even get a response. I never missed 1 payment but I am sitting with 1 month arrears.please get people who can do the work.The kind of work I'm doing my work is doing a credit check on me every month and this stupidity can cost me my job