Thanks for the reply.
My details are as follows:
1. IELTS- W:6, S: 7, L: 7.5, R: 7.5
2. Family member = 1
3. Funds = $13000
4. Completed Bachelors = June 2014
5. Eligible to work = August 2014
6. Work exp = Aug 2014 - Dec 2017
7. Canadian Master = Jan 2018 - Aug 2019
I don't know the reason...