Ezoic allows you to block certain advertisers from showing ads on your site. Publishers typically do this if there is a specific advertisement that they don't like, or if they would like to avoid showing a competitor's advertisement.
Log into your Ezoic dashboard and navigate to 'Monetization' > 'Advertiser Blocker' and 'Install App'. You can then enter the domain name of any advertisers (one per line) that you wish to block from displaying inventory on your site(s):
Remember to click 'Save' in order to confirm the changes you've made!