Hello@Mamf77 , 

It is recommend to remove Schedule / Away Mode/ Timer settings on tapo bulb in case those settings affects the bulb: 

https://www.tp-link.com/support/faq/2815/

Do you use any third party software or share this devices with others before, you could stop the sharing by guide here: 

It is recommended to remove the device in Alexa or any third party apps as well. Aslo confirm device firmware and app are both up to date. 

If still the same issue, may I know do you use any third party smart home software control the bulb? How often bulb turn on itself, if issue persists, please record the exact time when that happens in your time zone and let us know the time, thank you. 

Hey@Mamf77 ,Thank you for the details!

1> It is suggested trying a factory reset on the smart bulb, to help isolate the issue,  please  connect bulb to a Guest WiFi (or isolated wifi) from router and see if that helps * Note : only leave smart bulb connect to that Guest wifi if possible, other devices including your phone use the main WiFi, not the guest. 

RESET: https://www.tp-link.com/support/faq/2753/

2> Please also try a different light fixture.

If the issue persist, can you help provide more details: 

• May I know when did you purchase the bulb when did the issue occurs, did you recently add any new device in your network? 
• Can I know your current time zone, and the exact time again next time bulb turns on 
• the model of your router, does bulb connect to the router directly or through extenders.
• model of your phone and its IOS/ Android version:
• APP version: 

Thank you in advance!