What causes these patchwork lines in the resulting image from my scanner?

I’m trying to scan some old trading cards (AD&D Trading Cards from 1991) and I’m having trouble getting a good scan result on a flat bed scanner.

The issue I’m having is the resulting image appears as a patchwork that is not lined up properly.

Here is a zoomed in portion of a 1200dpi scan on my Canon CanoScan LiDE 210:

enter image description here

I tried buying a more recent scanner, an Epson Perfection V39 with the same problem but with a different representation or place:

enter image description here

What is causing this artifact across manufacturers?