Is "error three sd2" the literal message?
How exactly are you trying to make the payment?
If you're using the app then try the website instead - or vice versa.
E.g. try the web interface here:
Were you ever able to make a payment/purchase on 48 with this card?
What about on other online sites?
Has anything changed with the card - e.g. new card or changed details?
If you need to contact 48 support about this then see the links in my signature below.
You might (also) need to contact your bank to figure out why the transaction is failing.
