Unsure of who money belongs to

Assalamualaikum Hazrat Mufti Saheb. may Allah grant you long life.
I purchased some goods. I made payment via internet bank transfer.

The supplier received payment and confirmed receipt of money.

A few days later the amount was credited back into my account with the following reason ?account unknown.

I checked with the supplier and he checked with his bank he said payment was done.

I checked with my bank and they say the account I transferred to is incorrect. !

Who does this money belong to?

Was Salaam