Seems fake players breaking blocks is prevented from island grief prevention. As it works in nether or anyplace not an island.
The protection system requires you to allow them: Flags · MinecraftPortCentral/GriefPrevention Wiki · GitHub
Hi BloodRedOne, I hope you saw my response to your ticket. I spoke to our Admins and Consultants, who are aware of the issue and will be looking into it. As mentioned in the ticket, trusting the fake player is the first step. Since it appears that does not work, the Admins let me know that there is something they can try on our end. Since you have a ticket open, I will go ahead and close this thread. I'm sorry for any confusion and frustration this may have caused you. We will get this sorted out for you! Thank you for your patience as we figure this out. -Tipsied