sorry for late reply...
based on wad they told me:
1. the cash-back for my case is calculated frm 23 Feb - 22 Apr, 23 Apr - 22 Jul, 23 Jul - 22 Oct, 23 Oct - 31 Dec
2. i spent $2500 during statement mth of 23 Feb - 22 Mar, so i'm given $51+ for cash back (2%)
3. i spend a total of $1270 during statment mth of 23 Mar - 22 Apr, so i'm given $12+ for cash back (1%)
based on the above calculation, the cash back is correct.
so now i have to wait towards the end of july to chk whether the cash back given for period of 23 Apr - 22 Jul is correct or nt......

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