Play Montage in BeginPlay event Failed

I play montage in BeginPlay Event of the Character Bluerprint.But nothing happen.So I move the code from beginplay to tick event,still faied,and when I add a 1s delay,it play fine.
I think it is because the Character is not fully initialize in beginplay event.
Well,where should I put the playmontage code.

It’s my fault,I place a AI Component in my character blueprint,and int this Component’s begin play event,it will stop all montage!