Paid for but not received goods (refusing to release)

Came into store this morning to purchase router. First absa machines decline card. Then use fnb machine to pay using scan to pay, machine times out but payment shows paid on my account. Employees then reset the machine after receiving slip that says check another machine. Call manager, manager is unhelpful, phoned my pvt banker to check if payment went through as if failed would have reversed immediately, banker tells him payment is through and he needs to phone the fnb card machine division, he proceeds to tell the fnb banker that she doesn't know what she is talking about amd lectures her about her job. Spent 1.5 hrs in shop trying to sort out. He got off phone amd eventually listened and is currently hopefully phoning the card machine division, don't know as I told him I am not leaving without my product as it is paid for, and I will not make a double payment. Very unprofessional manager, used them 3x now, 1st was poor, 2nd was good, but this is unacceptable. Train your managing and counter staff!