Texture Loss after Build All Levels in Unreal

After “Build All Levels” my assets (surfaces and 3D_Assets) loses connection with texture and my mannequin disappears. My textured surface becomes a series of dark blocks and my 3D_assets become dark spots devoid of texture. Additionally, my mannequin becomes non-visible in the world I created. This happens every time I build. How can I reconnect the texture without having to start over?