Refund from purchase but no cn to be created

I need some problem, and hope you can help me.

I make payment for purchase, then received invoice with different amount (smaller)
Now, they refund the difference to my account. How do write this off? When i try to add refund through bank account, credit note has been created, but i do not want CN as amount on invoice is correct.

Thanks, Malgo

It is a credit note though, you paid one amount and then received a refund after receiving a revised invoice.

So you would enter the original invoice at the initial price, pay this from the bank, then return to the invoice and issue a partial credit note and nominated the bank account to deposit the refund to.