Adjusting Achors with - + lost precision (change path/seection tool)

[laurav54246517]

Hey guys I'm stuck, 

and i already apologize for this probably overdone beginner question, but I did not manage to find a right response elsewere. I might use wrong keywords, so i'll try explain in sentences:

I am trying to edit a path in Illustrator 2017, which I never had any problem to do the last 3 years. 

I select Selection Tool with Shortcut A, click on the anchors and levers to pull them in position i need. If i need more precision in adjusting, than my hands can get my mouse to do, I use + and - after I selected anchors after I zoomed in. 

So far so good. 

Today is different:

Using + and - will make the anchors jump in huge steps and also with the mouse I'm not able to move the ancors and its levers prechisely to the place I wished them to. 

I have no idea why?

Did I accidently change settings by a shortcut Iam not aware of? Can I readjust the steps the anchors take when changing their position back to the smoothness I was used before? I am lost. 

Already apprechiate your time and kindness of giving me a hint on this.  

[Monika Gause · Accepted solution]

This is a different file than the ones you previously edited?

Then check if Align to pixels or align to grid is turned on. If so: turn it off