"If we could do that, don't you think we'd have done that already?" Strange grumbles in return, letting out a small hmmph. "We'll try our best to free you, but it might take a while. It's only through special circumstances that I can talk to you in the first place."

He's a dumbass who got whammied by a plot item. It's only because Strange doesn't think before he does things that he's able to talk to Dark.