I have a Epson 3800 printer. Two month ago I did manual nozzle check (all perfect) and some prints.
Now I wanted to print again and did a manual nozzle check before I started. Result: nothing on the paper at all.

Ok, I thought it's time to clean up the print head by using window-leaner and the common procedure with a flat textile soaked with it under the print head for awhile. Result: only some lines visible on the paper after the manual nozzle check.
OK, more time, more cleaner... Result: the same.

Than I did two auto nuzzle checks. Result Error of the printer
And two power cleaning circles. Result: Only a few lines lines visible. And surprisingly: No ink in the maintenance tank but the printer shows me almost empty cartridges after the cleaning-circles. And no inkl visible in the printer.

Any idea what is happening here?