Hello everyone on the forum! 

The iOS app informed me that an update was available for my NVR. When I clicked to update, the device automatically downloaded the firmware version, installed it, and then restarted. From then on, it started having problems. It always freezes on the TP-LINK screen. The few times it boots normally, it either freezes or when I downgrade the update, it says there was a failure verifying the firmware file. Other times, it says the file is already updated. I've tried the steps suggested by TPLink, connecting via a network cable and changing my notebook's IP address, but I always have the same problems when trying to downgrade the firmware. Could someone help me? Has anyone experienced something similar? Thank you all.