Problem with re-signing released players.

I try to resign a player, who i released at the beginning of the season. I'm in the playoffs right now.
I sent a siging offer and the reply says, that i have no roster space. I have all three IR spots available.

Is it even possible to re-sign them?

Thanks in advance.

how is your salary cap ?

It's -10M.. That's the problem?

That would be the problem. Sometimes the wrong message is displayed on the PDA when you are unable to sign free agents for one reason or another, thus the game sometimes claims you have no roster space when it should tell you that you do not have the cap space.