MBZ C250 clock problem

  mercedes/c-class/2008-2015

We have a 2013 MBZ  C250, Starts and runs fine, but the clock display on the instrument cluster display is frozen.

Symptoms:  When car is started the clock displays the time it was started last.  Then, after a few seconds, time display changes to the current time.  This display doesn't change - stays frozen at the time car was started.

When I try to reset the time using the settings options, "set time" is grayed out.  All other settings and display options seem to work correctly.

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