Many modern ads are served over secure HTTPS connections. If your adblocker isn't inspecting these secure "tunnels," it won't see the ads. Note that some versions of 1DM may struggle with this if they don't trust user certificates.
The default blocklists included with 1DM are updated periodically. If you installed the app six months ago and never manually refreshed the lists, modern ads will sail right through. Advertisers constantly change domain names to bypass blockers. 1dm adblock not working
Check your Whitelist or Allowed Sites list in the Adblock settings. Remove any sites you didn't mean to add. 4. Deal with "Anti-Adblock" Scripts Many modern ads are served over secure HTTPS connections