Interface (call?) Problem

Hey folks,

I have a kinda HUGE problem
I made a blueprint Interface (Interface_BP), a player controller (PCont_BP) and a widget (MainWidget_BP).

In the Interface_BP I made a ConstructBuilding function
In the MainWidget_BP I set up a button with a ConstructBuilding Message with as target a reference to the PCont_BP
In the PCont_BP I set up an EventConstructBuilding

However the PCont_BP is not receiving the message any ideas?

Target reference wasnt exposed which caused the problem

Pretty sure @Allar can help

Sounds like he already figured it out. Nothing I can do.