If you have 2FA disabled on your account you need 6 digit code received via SMS to be able to sign in. If you are not receiving the SMS please check if the last few digits on the sign in page match the last few digits of your telephone number.
If the number is correct, please wait a few minutes before repeating the sign-in, as the SMS sometimes comes with he delay. Also, please make sure you are able to receive the international SMSes.
If the number does note match, or the SMS is not received after a few trys please contact the support service.