Thanks for reporting this!

See aebc1f9: the tool looks for images in Category:Images from Wiki Loves Earth 2021 in <country>. Back in 2018, it appeared the naming scheme for the Armenia categories was Images from Wiki Loves Monuments in Armenia & Nagorno-Karabakh, and so I changed the tool to expect categories with that name. Meanwhile, some categories are just Images_from_Wiki_Loves_Earth_2021_in_Armenia, so I have to make another exception to handle that :) Perhaps I should now change the default back to be just Armenia − happy to hear thoughts about it.

Exception for WLE 2021 is now deployed and things appear to be working − see https://wikiloves.toolforge.org/earth/2021/Armenia