Don't forget there are two adjustments for the Kia Cee'd Handbrake - one at the wheels and one at the handbrake lever.
First remove the rear road wheels and take out the Rubber Bung in the donut shaped bit of the disc. Rotate the wheels till the bung hole is at approx six o clock. Use a torch to identify the notched adjusting wheel visible through the bung hole, and using a screw driver blade, rotate the adjusting wheel until the brakes are locked on (unable to rotate the disc). Back off the adjusting wheel 5 notches, and check the disc hubs rotate freely. When complete both sides, replace the bungs, and put the road wheels back on, but leave the vehicle on the axle stands.
Second step is to check the handbrake lever. Without pressing the release button, pull the handbrake up until it is fully on, counting the number of clicks as you do so. There should be 7 clicks for a correctly adjusted cable. With the hand brake applied, go to each rear wheel and check they are locked. Then release the handbrake and check both rear wheels rotate freely. If the handbrake lever needs adjusting follow the video above.