Diagnosis
The infrared (IR) LEDs are illuminating, but the camera's night vision sensor or lens is blocked or misaligned. Often, it's a simple reflection or obstruction.
How to Fix It
First, clean the lens dome gently with a microfiber cloth. Look for a tiny, clear plastic ring around the lens—that's the IR cut filter that moves. Gently tap the side of the camera. Sometimes this filter gets stuck in the day position. If you hear a faint click and night vision starts working, that was it. Also, check for anything reflective directly in front of the camera (a window, shiny metal, a white wall too close) that's bouncing the IR light back and blinding the sensor.
If That Didn't Work
Go into the camera's settings in the Wyze app. Under Night Vision, make sure it's set to "Auto" and not forcibly set to "Off." Also, toggle the setting between "Auto" and "On" to see if it kicks the filter into gear.
Heads Up
If you have an after-market lens cover or a thick, third-party silicone case on the camera, it can block or diffuse the IR light enough to make the image pitch black. Try removing any accessories and testing again.