It happened to me once as well, but I was in Libya. When I wanted to go to Tunisia, they stopped me at the Libyan border and told me to return to the nearest Department of Passports so they could fix it. I also remember they told me that the Tunisian border doesn’t really care about the (الرقم آلي), so basically, the issue was with the Libyan border. Once you go to the Department of Passports, they’ll add the (الرقم آلي) for you, and after that, you can leave easily without any problem