In our system, calls must be assigned to its user in order to appear in the interface. When a user that can be assigned is not found, the call is assigned to the system admin. If the free seat is an operation, users' agentids must be defined correctly. If not free seat, phone number and / or agentid must be defined. This information of the user who has not been assigned to its call is checked. The call information is compared with the user who is thought to be assigned. If the custom data are not taken from the CTI, it is not possible to make an assignment.