i fell down a mountain and lived but lost my help when i try to get a new one they tell me that i already have help

You mean your companion/hired mercenary? Fast travel somewhere and they should spawn next to you or find another way to dismiss your companions.

Fast travel somewhere, they should appear.

Or wait one hour.

There's a mod for that ( that fixes it )

You should Fus Ro Da your companion off the mountain for not following

I had a follower disappear once while walking through a door, It took about 2 skyrim months for her to randomly appear, my sister lost hers at a bandit place, after she fast traveled to where she lost her follower they reappeared

I think after a set amount of time, followers return to wherever you found them.