Start with the safe check: The Hue bulb turns on normally but the Hue Bridge cannot discover it
Confirm you are adding it through the Bridge-based home in the Hue app and that the Bridge itself is online.
Run the next safe step: The Hue bulb turns on normally but the Hue Bridge cannot discover it
Run Add light once with the bulb powered. If discovery fails, enter the bulb serial number in the Hue app’s supported search flow and keep the bulb/Bridge reasonably close during pairing.
What success looks like: The Hue bulb turns on normally but the Hue Bridge cannot discover it
The bulb appears once in the Hue app and responds to on/off and brightness commands from its normal location.
Stop and escalate: The Hue bulb turns on normally but the Hue Bridge cannot discover it
If serial-number search also fails, follow Philips Hue’s model/product reset or support instructions. Avoid generic power-toggle reset sequences from unrelated Hue generations.