Outstanding amount

Hi.
I got an email from O2 and it's about the outstanding amount. But the problem is i don't live in germany or any europe anymore since last febuary. After I leaved germany, i totally forgot about my sim card which was used in there. Should I pay this outstanding amount?
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Dear Ms. Choi,

You have given us a direct debit mandate. However, the debit has been rejected by your bank.

This results in the following open amount: 13.94 €

Please balance the amount within the next three days.

0176xxxxxx5204 can be re-enabled, please use recharging cards. These are available from many trading partners.

Your connection will be activated immediately after clearing the outstanding amount.

After clearing your credit account, we use the direct debit procedure again.

If the payment has already been made, please consider this e-mail as meaningless.
regards

Your o2 team


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