HP PageWide Pro 477dw MFP smudges pages, what's the problem?

Question

HP

The printer began to print very strangely and smudge sheets



This behavior is observed only with duplex printing There is a
CISS and chips on cartridges (self-resetting)

There are two such printers and this problem appeared at about the same time

Run all possible cleanings from the printer settings - nothing changes
Tried feed paper through trays 1 and 2 - no difference
Wash the duplexer first

Answer 1

The question is closed.
The problem is paper. It would seem, SvetoCopy, and such problems.