Sam2021

W204, 2010. The climate control system behaves very strange after the recent service by the dealer. Temperature of the left side vents are little bit warmer than the right side in the MONO mode. Also when turn to hot (around 30 Centigrade) the down blowing air in the right side is still very cold while the left side is hot as it should be. In the defrost mode only the blower sound comes but no air is delivered to the windshield. I tried with resetting the system by pressing the defrost and recirc buttons simultaneously after turning the ignition switch to no. 2 position but the system just ignored and continue working as it was. Can any body suggest me how to reset the system. Thank you in advance