Strange shadowing when I bake

Realtime https://my.mixtape.moe/hdwoen.PNG

Baked https://my.mixtape.moe/zeqtqo.PNG

I noticed this is caused by the mesh normals, and this only appear when the mesh have a smooth applied:

https://my.mixtape.moe/aeuovx.PNG

But looks perfectly with a flat shading. The thing is I use a normal map for a less sharp edges looking, but the baked ignore the normal map texture, and have this behavior caused the mesh normals. There isn't a way I can have a correct shading with the normal map applied using the smooth mesh? I export the tangents on the mesh and I have "import" option fixed in the normals option of the model, of course the wall is static.