Are there users in your Teamleader account that should only have access to deals they are responsible for? Discover how limited deal access works here.
If you set limited deal access for a co-worker, they can only see deals that have been assigned to them or deals of clients of which they are account manager.
An admin user can change these settings by navigating to Settings > HR and clicking on the pencil next to the name of the co-worker. Then the slider 'Limited deal access' below deals need to be activated.
Limited deal access differs from limited CRM access and cannot be combined with it. Read here about the difference between limited deal access and limited CRM access.