Datefield.

Hallo Together,I have implemented two Datefield( Datefield_1 and Datefield_2)  Image may be NSFW.
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I  receive a mistake when the  Second Datefield smaller als the First Datefield.Image may be NSFW.
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to solvethis problem.jhave triedtouse the following code Image may be NSFW.
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Image may be NSFW.
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Unfortunatelythe code doesnotfunctionne

Please can you help me

Thanks

Eric