When purchasing an item on GamerPay, 3DS is forced and you will be required to authorize the payment through a 3DS validation. In most countries, it is either through an app on your Mobile Phone or a One-time password 📱
3-D Secure explained
The basic concept of the protocol is to tie the financial authorization process with online authentication. This additional security authentication is based on a three-domain model (hence the 3-D in the name itself). The three domains are:
Acquirer domain (the bank and the merchant to which the money is being paid).
Issuer domain (the card issuer of the card being used).
Interoperability domain (the infrastructure provided by the card scheme, credit, debit, prepaid or other types of payment card, to support the 3-D Secure protocol). It includes the Internet, merchant plug-in, access control server, and other software providers