When you go to different time zone, say Europe after Asia, 6 hrs earlier, all your sleep data history is converted to new time zone.
So my fell asleep time becomes like 1600 instead of 2000 what is was.
All your new sleep data is now recorded as went to sleep late since it compares to now wrong history.

Can you please fix, a lot of people travel these days?

Summarize: New data is recorded correct but it should not convert history to new zone.