Gear change

[wac1]

I have a 4 month old teocali comp with the slx rear derailer and deore ratchet . When the front ring is on the smallest and you change up gears on the rear it works fine . when you change down on the rear gears it jumps the gear and does not change down until you click it again .

 

When you reset the cable for a good down shift the up shift goes for a ball of      !@!@#. The shift works fine up and down as soon as you go to the next two front chain rings .

 

The shop replaced the inner and outer cable today saying it is fine but it still does the same thing . Any help Please .