Insurance of the phone

I have a clothing account with Foschini store. On the 11th July 2018 I bought one 35 Huawei P20 cell phone. On the 29/10/2020 received statement of R717 to be paid so I was surprise why my installment is so high then I called Foschini customer care to query the balance the person I spoke to her checked and she said to me I have been paying insurance for 2 phones since 2018 and on the system shows that I have bought only one phone but I'm paying insurance of two phones.