every door works kind of like this one I´ve attached
add a doOnce node or set a bool variable in your first interaction and check that also (AND) in the branch after you Trace (if you go for variable continue reading:)
Stop using all that cast nodes 
use a BP Interface. Its a 30sek effort and saves you a lot of headages. In your special case if you don’t want to use Interfaces, add a parent to all your door bps, implement the openDoor function in that parent (there you can also do your doOnce or Bool Variable checks) and cast not to the doors but to the parent, and call that function.
Hey Adnoh, thanks for the quick answer 
so I tried it with the doOnce node but the problem with that is, that I can´t use any other door after I used one of them 
and I if I give it a reset value, then I get the same problem, that I had before, the animation of a door will start over again everytime I press F at the door
I’m Not on the Computer Till monday i guess so I can’t Show you Code. What I mean ist Put the do once in your openDoor Event. Also the setanimationnode. And If you make all your Doors to have the Same Parent, you only need to do that once in that Parent. As all of your Doors are a Child instance, they would all Run their own openDoor Event - exactly one time only
Now it works like a charm! or atleast as I wanted it to work ^^ thank you very much Adnoh for your quick and REALLY helpful answers.