Unpaid debit order fee for their consultants mistake

I contacted the RCS call centre on 22 February to change my debit order date from 1st to 25th. I was told that it’s too late to change it for this month but it would be changed from next month going forward. However I was debited earlier on 26th February instead of the 1st March like the consultant told me. The funds was not yet available in my account (because the consultant told me that I would be debited on 1st March) and now I have an unpaid debit order on my account.

I contacted Rcs to refund the unpaid debit order fee since it was their consultants mistake for telling me that I would only be debited on 1st March. They told me to send my bank statement which I emailed. Today I receive a response that there is no refund due. I am beyond upset. They are negatively influencing my account and now they refuse to rectify their mistake and refund the unpaid fee.

I do not recommend RCS to anyone. Their customer service is terrible.