No response, no assistance!!!!

I have been calling the call centre from 27 May 2021 regarding a debit order which was supposed to be debited from my account on 25 May. I have made numerous calls, sent numerous emails and still not have received any assistance. They say they will call back, no calls received. I cannot believe that I must be so inconvenienced in trying to get this debit order deducted. It's absolutely frustrating. This is an error on Fidelity securedrives side yet I am left with this burden. Absolutely unacceptable service. I am so disgusted