How do i undo this aqualock on a dishwasher inlet??

Before i have water everywhere…. how do i get this connector off??
Is t press the yellow button and turn??

I would be using the blue isolator lever on the ball valve first before removing the hose.

turn the blue isolation tap to horizontal first as sandwich says.

Then press the yellow lever down to enable you to unscrew the top half of the connector from the chrome valve. The yellow lever is a lock to prevent the connector unscrewing itself.

Thanks.. Being a spaz.
It’s almost like a child proof lock.
Can never undo them either.

All sorted now