I haven't done this in a long time. Hopefully, someone with more knowledge will answer, but you might have to do something in /etc/httpd/conf.d--there may be a file in there that needs editing.
Other things to try.
This also looks promising.
I'm not sure what searching you may have done on your own, but these both came up googling phpadmin on fedora
Note that I didn't even google it correctly, leaving out the "My"