some thing interesting with tag

I installed https://www.neato.co.nz/ultimate-tag-warrior/

i got many error , i posted so many post here for help finally i found its problem with permalink structure

i have custom permalink structure

Some thing like this :/%categoty%/%postname%/

When i have above permalink structure i get error (404) if i on the url to show some thing like this domain.com/tag/tagname, but i am able to show the tag some thing like this https://www.domain.com/index.php?tag=tag name

If i change the permalink structure any thing given common option in word press i don’t get any error to show my tag
as domain.com/tag/tagname

do any one face this problem ?