Hetzner froze my account because I owed them 0.02 EURO's. It was not possible to pay it with a VISA credit or VISA debit, nor Amex card. They required me to wire transfer the money. However my bank does not allow the wiring of a 0.02 EURO amount, as the amount is too low.
Out of pure spite I built my own data center.
How did you build your own data center? Is it in your house, or renting a place somewhere? How much did it cost?
I would be curious about any details you can share.
Did you try to send them 20€ and request refund of excessive amount?