Quadplane 4.1.2 mode change to manual then Q_loiter in auto flights

Hi,
I am flying Quad plane with firmware version (4.1.2). Today I flew in AUTO cruise mode but suddenly in mid grid, system changed its mode to Q_LOITER. Can anybody help me. I have attached Telemetry log of this flight.
Thanks

https://drive.google.com/file/d/1NB2MzPuLL_KBPZXN7QFMNi50HfyEkE4M/view?usp=sharing