Tried to block internet access for one of my iPhone for testing purpose (it has dummy SIM means no cellular data)
Enable Parental Controls (i.e it is ON)
Choose a specific home device that I want to block then choose option : "Always" ,,,,,,,,,,,,my router screenshot same as the link above
Click Apply
But it didn't work !!!!
Tried another iphone same issue
I have latest firmware and I did restart the router as well
Am I missing something ?