You can see how to pin the icon to your toolbar here: https://help.adblockplus.org/hc/en-us/articles/4402461029779-Hide-or-show-the-Adblock-Plus-icon-on-your-browser-s-toolbar

If those steps don't help, please submit a support request and we'll be happy to assist you: https://help.adblockplus.org/hc/en-us/requests/new.