Increment Float Issue

My question refers to the longer bit of code in the top part of the image.
I’m trying to set the variable “Number of Tunnels Destroyed” so that each time the overlap event triggers the value will increment by one. The default is 0. When it triggers the first time it prints “1” as expected. However, it continues to only print 1 over and over and never increments.

The rest of the code is sort of extraneous to this problem. I tried going directly from overlap to increment and print and it was the same. I tested other some other scenarios to see if I could get increment float to work correctly and it did but… it just won’t work here.

Perhaps on an unrelated note but another quick question is that the animation of the blueprint wires firing during play testing won’t show up here but will in my other blueprints. But, I know it is firing because more tunnels are being spawned. Just curious why that is.

Thanks for taking the time to help~