Update fedora from 29 to 31,but getting 29 conflicting requests

,

In the worst case your can firstly backup everything of value, then reinstall Fedora (preferably not touching /home), then dnf upgrade.

Finally-also: Your can make a list of all installed packages with something like:

# dnf creates list
# awk takes only package names
# tail skips first line with word "Installed"
# sed removes .x86_64 .noarch et all.
# final output stored in my_treasures.txt
dnf list --installed |\
    awk '{print $1}' |\
    tail -n+2        |\
    sed 's@\(.\+\)\(\..\+\)@\1@' >\
    my_treasures.txt
# install it all with
dnf install `cat my_treasures.txt`