I have inconsitant shadows falling on two surfaces

Hey guys i have an issue with lightmaps/shadows. I have created 3 walls in a group inside 3ds max and created UV channels 1 and 2. When i export the wall into unreal engine 4 i increased the lightmap resolution to 1024 and pressed build. I get a problem when one shadow covers 2 walls as the shadow does not build in the correct place when the two walls meet. I have provided a picture of the issue

If anybody can please help me i would be really appreciative!

Make sure in the lightmap uv’s the two walls are connected. Everything that is connected can’t really go wrong. Try to connect as much as you can. It can this save up some uv space and will give you much better results.