What exactly do you mean by "credit" here?
You need an active membership AND cash credit on your account in order to be able to make international calls.
https://48.ie/charges/international-calls
Do you have both?
What happens when you try to call?
Any messages/error messages?
In order to contact 48 support see the link in my signature below or email them at support@48months.zendesk.com
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