Why do I get parameter does not exist in controller?

I am trying to create a jump animation, but every time I run the game I get a message saying parameter does not exist. Is it a bug, or am I missing something?

Here’s a screen shot:

Well it was a weird bug I guess? It seems to be working just fine now and no more errors out of no where, weird.

this is apparently an old and well known bug…i spend the last 2 weeks thinking my code was incorrect, checked everything, double checked, tried to find the solution only to learn its an old bug that hasn’t been fixed in YEARS…

I currently have the issue is there nothing that can be done?