Time problem

[黄奇]

Hello!
When I refresh and build the segment with the API, the incoming time is 
inconsistent with the time of the segment, I want to ask why.
refresh :
startTime:1559808000000(2019-06-06 16:00:00)；endTime:1565337600000(2019-08-09 
16:00:00)
build:
endTime:1571587200000(2019-10-21 00:00:00)
What's the problem？Is it because it needs some configuration and I didn't match 
it？