Accessed None trying to read property K2Node_Event_DamageCauser". etc

I’m trying (following a tutorial) to make the “blocking” skill working only towards damage received from enemies opposite to the player.
The BP kinda works (with an initial delay) but i get the error in the title that probably is slowing the process:

Blueprint Runtime Error: “Accessed None trying to read property
K2Node_Event_DamageCauser”. Blueprint:
Player_Paladin Function: Execute
Ubergraph Player Paladin Graph:
EventGraph Node: Branch

i’m not sure why i’m experiencing issues with the built in event AnyDamage and referring to DamageCauser
Any suggestions?
alt text