Automatic form creation does not work

[JeroenTuinstra]

When you fill everything in and click on "Générer mon attestation" it doesn't do anything except go back to the postal code field. As if the postal code is wrong even though there is a check mark next to it.
Basically the form doesn't get generated. Tried it on both Edge and Firefox, both same results.

[JeroenTuinstra]

So basically there is an error in the form checking. It expects a 5 figures postal code. Yet postal codes in Belgium are only 4 digits long. This is just some poor programming as the form is for international travellers and their postal codes are not all the same size as the French.

[akien-mga]

A workaround is to pad the number with a leading zero. #2 should fix the issue (needs testing by developers).