I am not able to figure out why my calculation is not able to match the Bonus 1 (save) received for the month of Mar. I opened the account at the end of Mar.

30-Mar Deposit RM 1000
31-Mar Deposit RM 50000
31-Mar Bill 1 - RM 1
31-Mar Bill 2 - RM 1
31-Mar Bill 3 - RM 1
31-Mar Bill 4 - RM 1
31-Mar Bill 5 - RM 1
31-Mar Bill 6 - RM 1
31-Mar Annual Fees - RM 8
31-Mar Interest Credited  RM 0.07 >> Correct
15-Apr Bonus 1 (Save) RM 26.49 >> Wrong
15-Apr Bonus 2 (Pay) RM 11.03 >> Correct

My calculation:
Save ( MAB x 1.8% / 365 x 31)
= 25993.04 x 1.8% / 365 x 31
= 39.74

Pay ( MAB x 0.5% / 365 x 31)
= 25993.04 x 0.5% / 365 x 31
= 11.04

I could not get the right number for Bonus 1 (Save), is there anything wrong with my calculation?