284 Unclamp error Mazak VTC16C with M32B

Hi all,
I have a Mazak VTC16C with M32B control.

I am trying to manually unclamp the tool but I get an error '284 Unclamp imp.(spindle ori.unfi)' when I turn the key to unclamp

I have orientated the spindle and the S.Lock light is lit up but I still get the error.

What am I doing wrong?

Thanks in advance