Unable to export using commcare-export Tool

I see the URL in the traceback contains /a/fmoh-echis//a/fmoh-echis/ - looks like that section of the path is added twice. I see you're passing this to the command:

https://www.echisethiopia.org/a/fmoh-echis/

You might try dropping the last bit - instead querying

https://www.echisethiopia.org