O2 online bank transfer to recharge

I have sent an SMS to 56656, got their IBAN, and my transaction reference number (Verwendungszeck), then used that reference number to transfer money to O2 IBAN. I have (before online transfer)  opted for 150MB data option from my Mein O2. 

I did not receive any SMS confirming my recharge, so obviously Mein O2 also ways Wartet auf Aufladung.

Can anyone please tell me how long does it take for a certain scheme to be active, if I transferred the money using a ref. number to O2 account?

Note: it has been only 2 hours. But I just wanted to know how long more.