Mobile bill SEPA mandate

Hello,

few weeks ago I did a subscription to O2 Free M Flex (sim card for my ipad). During the registration at the shop, I also subscribed and signed SEPA mandate with my bank coordinates to pay automatically the invoices.

On July 3rd, I received from o2 team a confirmation mail that the invoice was going to be withdraw from my bank account.

However, on July 13th, I received an new email from telefonica.de intimidating to pay the bill in 3 working days.

I would like to know:

- is the automatic payment not working via SEPA?
- should I pay manually the invoice?

Thank you for the support,

best regards,

Luca