You most likely already have an account with us. You can try signing up with a different e-mailaddress or clicking on forgot password. Another reason could be that the address is not correctly filled in. Check to see whether the postal code is without a space between the letters and numbers. So 1234AB instead of 1234 AB. The website also only allows you to register with a dutch address. IF you do not have this, you can us our address to regsiter with. Nieuwegracht 94, 3512LX Utrecht.
If this does not solve the issue, please send us an email to info@babel.nl, then we will try to solve the issue.