WARNING: This page is about a different car, the 2018 Kia Forte5 and 2018 Kia Forte. However, it is still accessible from the selected car via links, so may be relevant.
Check for continuity between teh trunk lid open switch terminal.
Fig 1: Trunk Lid Open Switch Connector Terminals
Courtesy of KIA MOTORS AMERICA, INC.
If continuity is not specified, inspect the switch.
Fig 2: Trunk Lid Open Switch Terminal Continuity Chart