Atera strada dl3 bike rack not working

[Paddington]

Can anyone help me....i bought an atera strada dl3 bike rack in the autumn from roof box co. The intention was to secure a roof box to it. But the mechanism which seems to open and close the tow ball cup isn't working. So I can't get it open to sit on the tow ball.
ok so return it to the seller....but given the new design I had to remove the bike holders with a jigsaw (so now damaged).

 

[Pete C]

Did you follow the instructions explicitly. It works a certain way to avoid accidental release - I have to remind myself how it works if I haven’t used it in a while.

Pete

 

[Paddington]

Finally managed to get it working....with lots of help from utube. Quite complicated