Can't remove cd changer cassette

[SPR117T]

The cd cassette was empty, so I pressed the eject button, it openned, I filled it up and placed it back in the changer with the arrows aligned how it says on cassette. I select cd changer on the PCM and it says "NO CASSETTE", and now it won't eject.

It is not even trying. I removed top cover to check the eject button is deploying.CHECK
I checked fuses. CHECK
I can see a red light on in the changer unit so I know it has power.

Is there another way of ejecting the cassette?
If I disconnect the battery and reboot.....is there a radio code?
Is there a PCM reset button?

The car is a 2004 C4s and I have only had it a week. I have never seen the cd changer work.

[EvoSlayer]

These things can be a royal pain in the arse, I had a few problems with my cd changer a while back, one of which was what you describe. I had it plugged in to diagnostics which didn't show anything and ended up stumping up 230 quid on an exchange CDC-4 unit from OPC and its been fine since. I had gone through all the usual stuff like checking the optical cable for kinks/tight bends, pulling/replacing the fuses for the PCM and Amp and resetting the system by pressing 1,4 and 8 simultaneously all to no avail! You could just try turning it off and on again by removing power cable fom unit! - You need to remove plastic cover and cd unit bracket from car to access plugs if it's same as turbo.

Good Luck