Seamless 3D tiles

Hi! I’m trying to make a procedurally generated scenario for an endless runner game. To do so, I’ve done a 3D tile and I’m planning to instantiate it one after another. The problem is it does not look seamless. It looks like this:

I don’t know how to approach this problem as I am a beginner in game development. Any ideas?

Check your shaders and your light sources.