Your Sogexia card is indeed 3D Secure enabled.
What is 3D Secure?
3D Secure improves the security of your card online purchases by adding a verification step before payment approval. This ensures that the author of the payment is really you, and not a fraudster.
This step is not necessary for every online payment, only when the merchant requires it.
How does it work?
After entering your Sogexia card information on the website of a merchant requesting 3D Secure, your web browser will redirect you to the following page:
To validate the payment, you will then need to connect to your Sogexia online account (using the mobile application or by opening a new tab on your web browser*).
*if you choose to log into your Sogexia account from your web browser, be careful to do so by opening a new tab. Do not close the merchant's website otherwise the payment will not be taken into account.
Once connected, a page will appear asking you to validate or refuse the payment (example below):
By clicking on "Confirm", a new page will load on which you will have to enter a code received by SMS (example below):
If the code entered is correct, your payment will be validated.
You will then be able to return to the merchant's website to finalise your purchase.