3rd Person Power-Up Game with C++ (v4.9) SpwanVolume not working

Hello,

I had followed the 3rd Person Power-Up Game with C++ (v4.9) video. However, when I try to make the
SpwanVolume, there is nothing showing out. I have the identical codes as the instruction. The building also
gives not errors. I had tried everything. I am also used the BatteryPickup_BP. Could anyone give some
suggestion what can be happen for this problem ? Thanks a lot for helping.