Old Navitimer authenticity

This is my first watch ever. I bought an old Navitimer II A13022 off Chrono24, original papers and box included. The production year is supposedly 1993, and there’s a sticker with the serial & reference number (6690) on the box that match the watch.
The watch arrived and it looks beautiful, but some things stood out to me:

• The papers really didn’t contain any information, except the stamped “identification number” that does not correspond with the serial number on the watch.
• The…

Old Navitimer authenticity