Dotted Shaows in modular environment? (UE4.22.3)

Hi All,

I’m making my first modular environment in UE4.22.3 and I came across an issue when lining up assets together. I seem to be getting a dotted shadow line. I’m not sure what could be causing this. I’m fairly new to this engine so It could just be something I haven’t discovered yet.

Please let me know your thoughts.

Thanks in advance!