Heat does not blow but AC does

  mercedes/e-class/2003-2009

Recently, after the following error appeared, my heat in my car stopped to work. A local mechanic replaced the Auxiliary battery in my 2003 E320 Mercedes:
“Battery protection convenience functions temporarily unavailable.”

After the replacement of the battery, the aforementioned error did not reset, I took my car back to the shop, they were able to reset the error but heating system does not function as it should. I feel heat on the driver and passenger side vents but cold air comes from the two middle front vents. Additionally, the blower does not work. However, the blower works in AC mode.

The shop checked the blower as well but did not find any problem with it.

What could be wrong?

Pervaiz

17