Cannot restore the catalog

I have performed Photoshop backup procedure more or less regularly for years, sometimes incremental backup, sometimes full backup. For about 5 yrs I´ve been using the same portable drive for that.

The last time I made full backup was Oct 2020. Rather soon after that the computer got broken. Now I have a new computer and new Photoshop.

I try to restore the catalogue but face a problem: Photoshop says that the October backup is only incremental backup and that I should present previous 4 discs after that. Well all four (and more) previous backups are on the same portable drive but there still is only one backup.tly file and that is dated 26.10.2020.

What can I do to restore the catalog??