Greetings Mr. Sajib from Sydney, Australia
. After a loooong time i entered today in the forum and was going through some posts and saw your post.
Recently i applied for GCMS through my younger brother who is living in Canada and i used my Aussie debit card to pay for GCMS notes. Cozz all Aussie debit cards can be used for international transactions. It's not mandatory that you must use a credit card. So as your card was not accepted, you should chq with your bank whether there is any prb or not.
Raisa's Hubby