Steemit Account creation bug! "This phone number has already been used" when it wasn't. What can I do?

I am trying to create account for my wife, but I get this error

"This phone number has already been used"

I am 100% that this number wasn't used before. Also, the form was submitted just once.

I had the same problem with the creation of my own account and only the second phone number worked.
I think it's clearly a bug ( country code +48 )

And advice how can I reset her phone number please, obviously we don't have 10 phone numbers to use it.

Thanks for help.