Playing for two teams at the same time

I signed a player from CSKA Moscow on loan, and had an agreed future fee. Halfway along his spell loan, I offer this amount to CSKA, they ofcourse accept, the player accepts my offer and I sign him. However, no money exchanges hands, he is still listed at CSKA as if he is on loan, he has a different contract with me but I can't offer him a new one bevause it seems as if he is still on loan, just for three years instead of one season.

So, since I haven't paid them, I decide to offer them money again and buy him outright, they agree to a fee (higher than the initial agreed upon future fee) and I sign him...again. But, he now still appears at CSKA but not away on loan, and he plays for me and has two contracts with me (if you look at his profile under contracts, he has two active contracts with my club, none with CSKA). His value is zero and asking price is zero (I can't change it for some reason).

For European games, when CSKA and I play on the same day (most of the time) he becomes unavailable for me because he "is already involved in another match today". He literally plays for them AND for ME. But he is a key player and I can't use him in Europe. I can't even sell him because no club will offer more than zero Euros for him since his asking price is zero and it can't be changed.

Very similar issue with another player I "signed" from Santos...

Very, very annoying...