You mean the €10 cash credit disappeared?
Are you sure that it wasn't used to pay for services not covered by membership/add-on allowances?
E.g. interntional calls/texts, MMS messages, calls to "special" numbers (1850, 1890 etc.)?
Maybe you have membership auto renewal enabled and it was used to pay for that?
What does your My History page say about recent payments/purchases/topups?
http://www.48months.ie/my-48/my-history
If necessary ask 48 support:
http://www.48months.ie/help#contact-us
What exactly happens when you try to enter your card details?
What error message(s?)?
Hope this helps.
