Problem wiht find item in array of actors

hii everyone, i am new in the forum and UE4, i have a problem with find item in array of actors. when i start UE4 a error show up, because there is a problem with the touching actor, but i delete the node and create it again, then the problem is fixed. the conection with the node is correct, because a actor is toched and looked for in a array of actos, i don´t now why this problem show up.
thanks for the attencion.