To run Firmware 6.6.64, your UniFi Network Application (Controller) should be updated to at least version 7.5.x or newer. Older controllers often cannot provision the latest firmware correctly to the AP.
Based on the identifier , you are referring to the Ubiquiti UniFi U6-LR (Long Range) Access Point. u6lr latest firmware
Even with the latest firmware, the U6-LR has specific behaviors to watch for: To run Firmware 6
Yes. Use the UniFi Mobile App or SSH method described above. To run Firmware 6.6.64
Update your UniFi Network Application console to the newest stable version. If the problem persists, press and hold the physical reset button on the back of the U6-LR for 10 seconds while powered on to factory reset it, then re-adopt. 3. PoEFail / Power Cycle Issues Post-Update