Logs: Security "unable to qualify domain / host name (xxxx) unknown

I was scanning log files after a DE install of KDE Plasma for errors and came across this: Unable to qualify domain / host name (xxxx) unknown, using short name. Something called Sendmail-msp belts out an error. I came across this link in a google search, cron - sm-msp-queue says: unable to qualify my own domain name (xxx) -- using short name - Ask Ubuntu, as a source for help but after reading different queries I’m not sure what to do. Running a desktop Lenovo ideacentre 310s-08ASR using Mint Mate 20.2 x86_64

Okay, could you please elaborate what exactly your issue is?

Apparently by installing Plasma, there is a default mail daemon called Sendmail, Sendmail.mc file was not configured throwing out an error in sys.log. I disabled the service in terminal by navigating to /etc/init.d, then typed ./sendmail stop .