Any one know this strange situation?I was trying to rewrite locomotion system V1 ... This happened

I was learning that locomotion system V1 , I use the same assets, and I am trying to rewrite the blueprint , but something out of imagenation came out… In Anim BP, Before I link two part just like the first picture I posed,everything is normal,

But after I linked … everything changed… this man turned into a …whatever I dont know … Can anybody tell me what is going on …? really thanks for help