Double whammy fault

I am so confused... I did an order online for the Samsung Galaxy A54, a lovely agent called and assisted me with the sale... Everything was confirmed and I was waiting for the couriers... I received 2 sms's, 1 for the actual phone and plan, AND a 2nd order for the same phone with a different plan, which of course, I did NOT ORDER. I REFUSE TO BE HELD RESPONSIBLE FOR A 2ND CONTRACT THAT I DID NOT ASK FOR. I've been calling to cancel this HUGE error, i hold of for 30mins, then the line goes dead. Then hold on again, with NO Answer... This is urgent. I need it resolved ASAP before I get billed or charged for this, and before the couriers get herenwith an incorrect order.