Incompetence

I recently changed my account details as a client its my duty to call my service provider and update them on any changes I make as a client. So I called 140 as usual I communicated with the consultant telephonically and I explained to her that I'd like her to update my account details on their system for debit order purposes she agreed and I confirmed everything with her she said everything is fine.

Yesterday I received a text message (SMS) saying that my account is in arrears so I failed to understand this, because I made an effort to call them the least she could've done is to change my account details as per our conversation now my account is in arrears so how is that my problem that your employee failed to do her job that's not my problem. And if you block my SIM card we gonna have a problem cause I wont be making any financial arrangement with you guys I wont honestly.