Once a PSA is synced to your account, all the clients, opportunities, and Products are synced between PSA and Zomentum. If you wish to disconnect the PSA that is synced, you may do the same from Settings.
Head to Settings > Integration.
Please select the PSA > Disconnect.
Once disconnected, your clients, opportunities, and any documents related to the opportunities and products will no longer be synced between your PSA and Zomentum.