Error in updating

edit

This problem mainly occurs if you have duplicate packages. try and run the command -

# yum install yum-utils
# package-cleanup  -C -q --dupes  |wc -l

I guess you will only find one as you have pointed above (flash-plugin). Now do run the following commands

# su -
# package-cleanup --cleandupes

After this try doing your updates. Hopefully this should solve your issues