You need to provide more details!
Have you triggered RTH and you got that message? Have you manually disabled obstacle avoidance in the app?
Did you fly in low light conditions?
It is good you opened your own thread with this question.
It was not so nice that you were disrupting other threads with it...
I bet it was the sun giving problems to the sensors. The drone was facing at 8am almost 90° East. That's exactly where the sun is these days in your region.
Turn the drone away from the sun next time and you shouldn't have problems.
You know that you can still maneuver your drone upon RTH!?
It is just telling you that you won't have obstacle sensing when the aircraft is landing.
It's not about the RTH flight, just for the landing.
And it has nothing to do with the sun, cleaning sensors or poor light.