Theme won't update

Trying to update to latest version of Enfold and am receiving this error message:
An error occurred while updating Enfold: Could not remove the old theme.
I also see this:
Attention: We detected some custom styling rules in your custom.css file but could not restore it. Please open the file yourself and add the following content:
I didn’t make any custom CSS alterations so don’t know why I’m seeing this message or if it is related to previous message about system not removing old theme.
Thanks in advance for your assistance.