Question About 7 Zip

Greetings, I have been encountering a problem with 7 Zip, sometimes it does not allow to zip file. So I would like to uninstall it and then will install it again. But when I try to uninstall it, I cant. I am getting an error message.

I dont know what could be the issue. Does anyone have any idea about how can I able to fix it? Any kind of help would be highly appreciated.