If you are getting notifications from DigitGuild, then your Mac is infected with adware. DigitGuild is adware for Mac.
DigitGuild changes setting in your Mac. First, DigitGuild installs a browser extension in your browser. Then, after DigitGuild hijacks your browser, it modifies settings in the browser. For example, it changes the default home page, modifies search results, and displays unwanted pop-ups in your browser.