I had a problem with my kia ceed 2013 unit is same in sportage , unit model number 96560 ,headunit touchscreen worked only when i heated up car, found out digitizer on headunit is faulty.
If you have unresponsive or broken glass/ touchscreen on yours , you have few options, new unit feom Kia £700 , second hand of the ebay £250, or replace digitizer £25.i made video how to replace it:
There is a link under video to get new digitizer.
There is link where to get digitizer for this unit.
If you from around Oxfordshire then i will be maybe able to help you with replacing it.