I believe I have very unique situation - I want to be a new customer, and I filled a request form for SIM. In the request form Vodafone asked me about filling in IBAN number, so I did it.
When delivery guy came with my SIM, he couldn't be able to transfer SIM to me, cause I paid 0.01 Euro with card which doesn't have IBAN as a number. Unique, right? Of course it doesn't have! IBAN - is a bank account number, and card you're paying with has number from a payment system (Maestro, MasterCard, Visa, etc). So I payed with Maestro card, connected to IBAN registered with Vodafone, but in transaction IBAN has not been shown, therefore delivery guy said - sorry, it's not you, good bye.
I called to Vodafone customer support and they said "Oh, this is unique, I don't know, call Dyna delivery".
So I called Dyna delivery and they said "Oh, I don't know, this is unique, call Vodafone".
So Vodafone apparently doesn't know that you could have 10 different cards with different number and different payment systems connected to a single IBAN account. Cause yes, it's pretty unique!
I don't know what could be more awful customer experience for the new customer.