Car is in limp mode

What is your question?

I have a 07 Dodge Charger 5.7l hemi that has been in limp mode for a couple months now. I hooked my reader up to it and it gave my p3401, deactivation with cylinder 1, could this be my problem? I’ve tried almost everything to fix it. Last couple days it’s not wanting to shift gears mainly out of first and second and won’t let me go above 3000 rpm’s. If anybody knows why my car is doing this please let me know.

What makes this problem better or worse?

Doesn’t want to shift.

How long has your 2007 Dodge Charger had this problem?

Few months