Are the clothes parented to your character? Go into your character blueprint < Go into the viewport < See add component < Add your clothes(skeletal meshes) to this < Make sure they are parented to the character and not anything else. If you go in and set up sockets you can use the sections that is to the right(Details) under Sockets. This will make attaching things much easier. (This is still in the viewport section mentioned before) Sockets can be created in the skeleton and directly applied to it as well. This is what is usually used to make characters hold swords, shields, etc. I can link you my project so you can take a look at it. Disregard how I attached a small UE man to the character, it was just a easy way to use a skeletal mesh. Let me know if this helps.
-Thank you
