Problem with adding characters

I have a problem adding my own character to the game. Character made in blender. He writes to me that there is a skeleton problem, or could anyone advise on this?

You haven’t really posted enough information for anyone to help you. My best guess based on what you’re saying is that you’re trying to import onto an existing skeleton. That won’t work from Blender. Even an exported Epic skeleton needs to be imported with a new skeleton and then retarget your animations. Even if you 100% match the skeleton hierarchy, the bone orientations end up wrong and the animations won’t work.