paying into split up partner's bank account

My company does busness with a Turkish company.
We recently paid an invoice for materials. We paid to the account we usually paid to, but unfortunatly the two parteners had fallen out and split up in business terms. We did not get to the bank in time to stop the payment so the wrong partener got the money. He has refused to pay the money back.
I am now wanting to know were we stand, and how Turkish law views what i see as theft, although we are partially to blame.
I hope this form is filled in correctly and you can help
Thank you Geoff Galvin

Dear Guest,
According to our laws, you can want your money back. İf he doesn't give the money, you can file a case against him. İf the court decides that you are right, you can use that decision to have your money back.
But, to win the case, you have to prove that, you have given that money wrongly, and you must also prove that, this money isn't based on a tradition between your company and that company.

Need your answers to the followings before commenting on your case.

1- What sort of company is it? Seems like an ordinary partnership as you mentioned splitting up.

2- Are you sure indeed there was a split ? Did you see the papers?

3- You paid the invoice relating to delivered or undelivered goods?