UE4 C++ use SetSplinePoints() let the editor crash

I‘m trying to get the pathpoints from navigation to draw a pathline.
like this Creating Splines From Navigation Paths
and this Draw predicted movement path (and any spline trajectory)
but when I start runtime,the editor will certain crash.
I check code many times but still can’t found out why.but I guess there’s something wrong from SetSplinePoints() or ClearSplinePoints().
here’s my code:



and the error(I dont konw why so many “UnKownFunction”)

By the way,I thought is ue4.26.1’s wrong.but I update to ue4.26.2, it’s still no working.

Oh,God,I rename the Spline parameter and then rebuild,it finally works~~~
This is so strange. I think it’s something wrong when building,let the splinecomponent didn’t work.