Without any doubt it's a fake asking for money..
Instead, "UBLOCK ORIGIN", yes the 2 words "uBlock" and "Origin" when you search on google, is the REAL one! which ask for ... NOTHING
Uninstall this fake copy and search for "uBlock Origin by Raymond Hill" or go straight to: https://addons.mozilla.org/en-US/firefox/addon/ublock-origin/