Won’t shift in reverse

Hello, it would be important to have a Kia compatible diagnostic tool that can monitor gear shift lever position, shift solenoid commands, desired gear selected engagement from the transmission as recorded by the processor. If you are seeing commands to engage, and shift solenoid position changes and there is no engagement, then it could very well be an internal mechanical concern that is occurring, requiring tear down or replacement of the transmission. Seek the assistance of trusted skilled techs near you: https://repairpal.com/repair-shops/kia-repair-and-service-in-bakersfield-california