[EN] help me figure out the problem

hello guys, moved in germany the other week and i could use some help. i am trying to buy something online using my mobile phone's credit but the payament always gets declined and i receive an sms that reads:
"Aldi Talk Info: Bei Aufladung des Guthabens per SEPA-Lastschriftverfahren ist der Dienst Bezahlen per Handyrechnung zunaechst nur eingeschrankt verfuegbar"
i've tried translating it but to be honest it makes even less sense once it's translated. i think it's saying that my sim has been blocked?

Zitat von prepaid.

You have to buy credit in the Aldi Discounter and recharge. Then you can buy and pay online.

i already have 16€ on my card. the payament amounts to 12,99€ so i should totally be able to purchuase it. do i need to recharge even more money?

I did have the same problem having my bank account approved. Do write them a message or mail. Works flawless afterwards. It has nothing to do with the amount you charged with vouchers.