Heater blower MB W124 1991 200E

  mercedes/e-class/1996-2003

My MB has climate control (with buttons and one temp wheel). All works fine and than suddenly the blower stops. And after some time it works again like it should. It works for some hours and then some time not working at all. No strange noises or other problems when working. When not working then it’s only the air that is forced into cabine that is coming in. Air is hot as it should be.
And when it’s not blowing I can hear some noises when clicking buttons but no blowing at all.
Haven’t found anyone with the same problem yet.
No bad fuses. Combination relay just replaced.
Could it be some bad electronic plate?
Or the blower motor itself?
Has anyone any ideas?
Thank you!

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