Can't add order to Apple ID - SOLVED

I placed an order for an iPhone and payed using Apple Pay. For some reasons, the order wasn't added to my Apple ID even if I had to authenticate with my Apple ID. I looked for the Order Status using the order number and the email used and then I tried to add the order to my Apple ID. It asked me to sign in with my Apple ID and then to enter the phone number used when I placed the order. Here comes the issue, when I wrote my phone number, without the country code, it said something like "Please enter a valid phone number using only numbers".

The solution is:

Write your phone number without the 0 in front and add the country code without the 00 or +.

Let's say you're from UK and your phone number is 0792123456. The country code is +44 or 0044. Then write your number like this, 44792123456 and it will work.

Regards!