I am from the United States and am trying to reserve train tickets on the BAHN website. I am getting the following error message when I type in my phone number:

Please enter the number with country or area code.

I tried keying a 1 before the number, and that did not work either.

What should I be keying there assuming that my U.S. telephone number is 600-555-4444?

Thanks!

0016005554444

Thank you. It worked!