Q1. How do I update the firmware of the TP-Link camera?

1. On the Tapo app, you can go to Me>Firmware Update page to update the firmware or go to the camera's Device Settings>Firmware Update page to update the firmware.
Here are the detailed instructions: How to update the firmware of the Tapo & Kasa devices on the Tapo App?
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2. On the Kasa app, you can go to the Me>Firmware Update page to update the firmware.
Here are the detailed instructions: How to update firmware of Kasa smart devices?

Q2. What can I do if I fail to update the camera's firmware?

1. Reboot the camera.
2. Move the camera closer to the router and ensure the home router has an internet connection.
3. Disable the firewall or antivirus setting on the home router if there is one.
4. Try to update the firmware again

Q3. What can I do if the new firmware does not update on all cameras with the same model but only some cameras update?

1. Firstly, please check the hardware version of the camera. 
For example, you can go to the camera's Device Settings>Device Info page to find its hardware version. The link below introduces the detailed instructions to find the hardware version of your camera.
How to find the hardware version on a TP-Link device?

2. If the cameras' model number is the same but the hardware version is different, it's normal to see the cameras' firmware differently.

3. If the cameras' model number and hardware version are the same, since we roll out the new firmware gradually, it's reasonable to see that some cameras detect and update to the new firmware, but some do not. 
Don't worry the cameras with the old firmware version won't update, please wait patiently, and you can update the firmware on the Tapo/Kasa app once the new firmware has been pushed to the cameras.

More Article: 

What to do if my Tapo Camera gets bricked after a firmware update?