Blackboard Value is not being set to Player Pawn

I’m trying to set value of a Blackboard key to my Player Pawn in my AI blueprint but it is not setting the value of the blackboard key to my Player Pawn. In the play mode, the key is assigned “None” value.
Here is the photo of the Blackboard key:

Here is the photo is AI Blueprint:

Here is the result:

Note: I have set my own GameMode in the project settings and I have set my own character in Default Pawn.