Leakage from magenta nozzle

Hi Dana,
I have Cone inks in a 9890. There is much I could say as I am on my second head with this printer, but it’s a known story.
My current problem is the magenta nozzle clogging and leaking from the head assembly.
It started with a initial pattern check with the magenta pattern totally absent.
After multiple cleanings which included three power cleanings I got a full pattern from the magenta nozzle. The good news not a head failure.
Just so you know running multiple power cleanings is not a common practice.
Inspection of the cart shows no leakage.
After printing a 16x20 print, magenta pattern absent again. In some cases one pair cleaning would do the job, a couple of times in took a power cleaning to clear magenta nozzle for a full pattern.
As I continued to print after each printing of one print same event on nozzle check for magenta.
On the last print I had major drips of magenta that leaked from the nozzle.
I opened up the printer to find magenta running down the platen.
I cleaned resting and pumping pads and squeegee, applied piezo cleaning solution to pads and waited overnite with no results, magenta pattern absent.
My guess it is not a pump problem as all other nozzles are firing in full force.
Perhaps a damper problem with the magenta port to the nozzle.
I would appreciate any insight you might have to this problem.
Thanks
Russell