Phone: 0904 475 9500
I am from the US and use credit cards from US Banks. WizzAir is not able to process transactions from US Banks and makes no mention of this on their website.
After unsuccessfully trying to buy a ticket on their website, the only indicated reason was "transaction denied". So I called WizzAir, the call announcement informed me there would be a charge of $0.65 for each minute and a minimum of 5 minutes. My phone charge was $9.90 for 4 minutes. My normal phone rate is $0.022 per minute.
Calling WizzAir to learn why I could not pay for their ticket cost me near $10.