Use MPU6050 to get in back into Flat postion

[titolini72]

Hi All,
I'm pretty new in using MPU6050 and I end up to a dead end since misunderastnding of this library usage I guess.
My intend is to use MPU6050 within a Camera Gimbal. I succeed in configuration my STM32 and get YAw/Pitch/Roll value . Which fine indeed .... BUT
My system returns correct values as we put back MPU6050 into same position : flat position. However if the MPU6050 is in a random position (that may happened in my project) my Yaw/Picth/Roll values are issued from this random position. I was expecting Yaw/Picth/Roll angle value to get back to my initial positon : flat.
I did it something wrong but ... what ?

Thanks in advance for your help.
Regards