What exactly do you want help with?
If you're having trouble with roaming then see here:
https://community.48.ie/t5/The-Knowledgebase/The-Roaming-Troubleshooting-Guide/ta-p/52179
https://community.48.ie/t5/Internet/How-to-fix-no-network-service-when-roaming/td-p/56352
If that doesn't help then you'll have to contact 48 support.
See the link in my signature below or email them at support@48months.zendesk.com
I don't see how a new SIM delivered to an Irish address is going to help you while you're abroad.
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