Hey Luka, as counterpart0 discovers earlier in this post, his problem was that he was doing all the math in the pickup class itself. That’s a problem since each pickup is basically only keeping its own score when it gets picked up. What you need is for some other Blueprint (the character, the game, a separate actor) to keep track of when things get picked up, and increment the score from outside the pickup.
All of this is covered in the posts above. I even put in some pretty pictures! I hope they help! 
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