Does your cash credit balance show the €10 topup?
How are you trying to buy membership?
Via the app?
Via the website?
By text (http://community.48months.ie/t5/The-Knowledgebase/How-do-I-buy-stuff-by-text/ta-p/3974)?
Maybe try one of the other methods to see if it makes any difference?
Otherwise you'll probably need to contact 48 support - see the link in my signature below.
Hope this helps.
