Echo problems in open plan office

Hello,

I work in a small open plan office with four people and we've been trying to work out how to stop having echo problems when only some of us join a client Zoom call. So the example scenario is that the Zoom call is hosted by our client and two of us join with our headsets which have in built microphones (+ cameras which have in built microphones but these are switched off). We not only hear eachother through our microphones but also from opposite sides of the desk. There's also the issue of hearing other colleagues in the room who are not on the call. I'm guessing the solution is noise cancelling headphones with in built microphones so it's as if we're not in the same room but I'd be grateful for any other thoughts!