No because the devil was on e an angel. Angels know everything except about God. As such they know what they did was wrong and they did it anyway. That can't be forgiven, if we do that that is forgive but why's that? Because we are human. We aren't perfect, angels serve God. But a lot closer than us. That gives even more to know about God than us.
If they are dead and are in hell, they made their choice. They can't be forgiven. If they are still alive, if they are truly sorry for what they did and want to do better to live a life of Christ, then yes, they are forgiven.
But in the Netflix series LUCIFER, Lucifer was telling to a human that hell doors are always open and souls can leave anytime, but they don't want to, is that true?
No absolutely not. That's the devil working you corrupting you to leave God. He's saying yeah you can this sin and get sent to the firey place known as Hell, but you can leave and go to heaven. That's literal temptation.
He doesn't posses people. He tempts them so very quietly. He tempts you in ways where you don't say "that's the devil trying to steer me from God" No it's more like "God will forgive you if you do it. He's all forgiving just do it" but when you actually do it he turns a 180, saying "Look what you've done! God will never forgive this. You shouldn't even bother talking to him again. He'll never forgive you. He'll hate you" and that's where he gets you. If that works. Another poor souls joins him in eternal damnnation
