Digital BW, The Print

Hey out there,

maybe you have some advice for me, or maybe you have experienced the
same as I.
I recently (about 2 weeks ago) ordered a set of 8 funnel fill
cartridges  for my EPSON 4000 printer from MIS, along with some bulk ink.
As I received the carts and put them into the printer five of the
eight(!!) carts were not recognized by the printer. When I moved them
around a little bit it happened that the printer sporadically
recognized it, but lost it again. I managed that all the carts are
recognized now - but don't dare to touch them again...!

So I complained this poor quality via E-Mail to MIS. After 10 days of
silence I started complaining via the helpserve eSupport system.

Silence. 

So what is wrong? Aren't they interested in their customers? I can't
believe it!

What can I do now? Any thoughts?

Thank you,
Gerd.