Hi, I had the same problem as you too. I could not locate the MSOS (Maybank Secure Online Shopping) thingy via maybank2u.

So I called up the bank via their Maybank Group Customer Care at 1300 88 6688 or +603 7844 3696.

They registered my mobile number and said that I am good to go but I have to first increase my debit card purchase limit via Maybank2u.