The transfer unit was according to the counter worn out (Samsung Printer Diagnostics). So I bought a new one and replaced the old one. But to my amazement the counter doesn't get reset. How can this be?
As far as I know there is no way to reset the counters in printers like this one since they do not have a panel, you can try to update the firmware to see it that helps, however is a long shot and is not guaranteed to fix it. Here is a small guide https://www.youtube.com/watch?v=z1T9nWByNNM
Be alert for scammers posting fake support phone numbers and/or email addresses on the community. If you think you have received a fake HP Support message, please report it to us by clicking on "Flag Post".