Recently got our iMac Pro back from apple for screen repair, went to change out from table stand to put our vesa mount back on (we use a wall arm) - and the receiver piece suddenly retracted back in, trying to pull it out while engaging the lock doesn't help and sort of out of ideas
last resort will be sending it back to apple
see photo for ref
https://imgur.com/a/gXLpRlf
last resort will be sending it back to apple
see photo for ref
https://imgur.com/a/gXLpRlf