Accessed none getting physical material.

Hi there,

I have created a simple projectile that should read the physical material of an object that it collides with, then set a state in Wwise to play an impact sound depending on the material. The blueprint prints the correct physical material but does not change the state, it also generates this run time error:

Blueprint Runtime Error: Accessed None trying to read property CallFunc_GetMaterial_ReturnValue from function: ‘ExecuteUbergraph_Auto_Turret_Projectile’ from node: Print String in graph: EventGraph in object: Auto_Turret_Projectile with description: Accessed None trying to read property CallFunc_GetMaterial_ReturnValue

If anyone would be able to help me understand why this is happening i would greatly appreciate it!

Thanks