Hello Abhijit,
Thank you for visiting Microsoft Community and providing us with the detailed description about the issue.
As per the description, I understand that you are experiencing issue setting SQL server date time format. When you try to set the system date format id ddmmy, then the data is not stored in SQL server on the system.
In order to get more information regarding this issue, we have a dedicated forum where such issues are handled and would be better suited in the TechNet community.
Please visit the link below to find a community that will offer the best support.
I hope this information is helpful.
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Thank you.