Look like this question has come up before but didn't result in an answer, hence the new post.
https://www.alfaclubvic.org.au/forum/index.php/topic,12897.msg77594.html#msg77594
So, the gear linkage cable has come loose from the ball joint on the gearbox.
It appears that the clip (part no 46827488) has become worn or broken, so pops off the ball joint.
UK suppliers who list it (alfashop, alfaworkshop) say its no longer available. EB Spares don't have it.
It seems to be available at "partsinn" , i haven't used this supplier before
https://partsinn.lt/?oem=46827488
anyway, any advice from those who have needed this part before would be appreciated