A few things are sticking out to me here
it would appear from the one image that your using a behavior tree and blackboard
Try overriding the function “Event Receive Execute AI”
Or simply verifying the Above works when attached to “Begin Play”
Make sure you have a nav mesh in your level if your using “AiMoveTo” seems to be my understanding
Next make sure your behavior tree is actually running
In class defaults of your character make sure the AiController class is set properly to the Ai controller you should have made
Setup the behavior tree controller and task
Controller:
Behavior Tree:
Task:
This works flawlessly
all i have done that is not pictured here is put a NavMeshBoundsVolume in my level
you can visuallize the navigatable area by ai by pressing “P”
If this doesn’t solve your problem then it would mean you don’t have a valid vector in range of the NavMesh
you need a navmesh
or finally you cannot use AiMoveTo without it and will have to look at a different method of moving
Ex something simple i setup to show using Add Impulse another method of moving without navmesh
The resulting effect is every 1 second the player jumps
so you could get to the 1st point by adding impulse in the direction of the first point
rotate to face that direction get forward vector
Multiply this by how fast you wanna go
add some condition to check when your reasonably in range
find the next point and do the same
Also additional resources on the basics of how it all works
failing any of this extensive advice we’ll need more information 
Also worth noting make sure its a character type BP and not Pawn
If its Pawn make sure to do all the same things above but instead of having character movment component in the pawn you’d use FloatingPawnMovment
tested also works as jumping example or with AiMoveTo