You said Europe Internet was off! I take it that you mean international roaming data is off this is what needs to be on without it then it's wifi only. iPhones seem to be difficult fit virgin it seems.
If all these checks have been done and there's still a problem, I'll need to take your sister's details so that I can verify the settings on the account are correct. I'll send you a private message requesting further details. Just check the envelope icon at the top right of this page.
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