Were both top-ups done yesterday on the 18th or was one done on the 18th & the other today? Can you also confirm the date of your last top-up in December? This will help me explain better where your €15 credit went. If you could also log into your My3 account & check out the My Events section you'll be able to see if there were any charges in the last 24 hrs, let me know what those charges are for.
Thanks for the screenshot, the data charges confirm that before you topped up by €15 your plan had expired. When you're plan is not active you're charged €1.30c per MB. The charges are valid.
