Hello @Broeux 

After factory reset the camera, make sure you have reinstalled it in the Kasa APP. (Kasa APP> click on+ symbol to add a new device )

For 'can not turn on ' do you mean the camera itself is not powered on? If camera does not get any power, you could try a different power outage  or try a different power cord for the camera if you got one. 

If the camera works again but have trouble with SD card recording.  can you help confirm some case details below to look into your case further, thank you!

1.  photo of H2testw test result , this is to test if the SD card itself is fine  How to Verify Fake Micro SD Cards

2.  photo of SD card

3.  photo of the error on Kasa APP 

4.  Mac address & SN of camera (please share via private message)

5. Kasa APP version

Here is an instruction that helps with troubleshoot SD card problem, kindly give it a try and let us know if it works for you.

What should I do if the SD card doesn’t work properly on my camera?

Please also confirm Kasa APP and tapo Camera firmware are both up to date. 

Note if H2tesw has a warning or error, it is recommended to try a different SD card. 

 Hello  @Broeux 

Sorry for the late response, it's fine that the camera becomes grayed out or can't be turned on via APP. 

• Blinking amber/ Green means camera is in factory default state, and now you could re-add camera in the Kasa APP. 
• In Kasa app- click + icon on the right tap to add a new device and reinstall your camera in the kasa APP. 
• 

Here is the LED status explanation as the UG of EC70,  Blinking amber and green on the camera means Ready for setup on kasa camera, this is the correct light status after a reset, and next step is to reinstall your camera and go through setup process in the kasa app to relink camera to your home Wifi network