[CentOS] Advice in Time Sync

Dear all,

I would need some advice as I am a beginner in CentOS.

The question is as follows:

How to set up timing if NTP was block by ISP?

I have try many way such as link the timezone , getting from the hardware
clock.However , it is not the solution.

Please advice.

-- 
Regards,
Ku Wei Xiong
0166365831