your again not providing any new or useful information to work from. i get that you used the attach to component node with the target being the player and its socket that is in the hand. that does not imply that youve tried setting its location via a set location node. it also doesnt say any steps youve taken to try to remedy the situation or solutions that youve tried. it could literally be that you are attaching the gun but it is retaining its offset once its brought into local space. so you would end up with the gun moving with the hand but in an offset position in which case a simple solution is to set its location to the location of the socket. attaching to a component doesnt mean attaching and moving. you could also experiment with the location and scale settings to see if those affect it. When i first started out and was attaching to actors that was one issue that i ran into.
main point here is be descriptive and exact in what you say, and give information and feedback on what you try and the results that you get.