why ALBUM doesn't work? (404 error)

i just did a sample page,gallery works well.
but why album doesn’t work? 404 error.
of course i already put two galleries in one album.
see here:
https://blurfun.com/test/sfsd/

and here is backend pic:
https://www.blurfun.com/temp/web.jpg

Thanks a lot~

https://www.ads-software.com/extend/plugins/nextgen-gallery/