Dam Construction Permanently Halted

[Kung-Fu knight]

In my capital I tried to build a dam but switched construction to emergency build a unit. When I finished building I noticed that I couldn't finish construction on the dam despite it requiring one more turn. It still shows the progress bar and I haven't received any extra housing so it didn't stealth finish, it just wont let me select the dam again. I'm in the process of building an engineer to try and force build it, which is obviously not ideal.

Does anyone have any advice?

 

[Kaan Boztepe]

most likely someone else build a dam on the same river you are trying to built