1.3 cdti clutch won't bleed

My clutch biting point has got lower recently and then yesterday I had no clutch.
While having my fingers crossed hoping the release bearing hasn't gone through the pressure plate I thought maybe it's lost fluid and if I bleed it it will fix it.
I've had an easy bleed on the reservoir with plenty of brake fluid in, cracked off the bleed and no fluid coming out or emptying from the easy bleed. Removed the bleed plug completely and nothing. Checked it was clear, refitted a couple of turns and used a mityvac to create a vacuum on it still nothing. Regardless of if the clutch has gone or not it should bleed through. I'm thinking I have a clutch master cylinder problem, not taking in fluid.

What do you think?
Thanks