Getting ‘internal Server Error’ in ajax success when already i got the data from database

I was Request to return data from database using webApi call and i got the data in return of Jsonresult and When the Api Response is taking too much of time to return data from database, i got the data from database in return of Jsonresult success but didn’t got that data in ajax sucesss. it show ‘Internal Server Error’ with status 500

This is the Image that showing the list of data return from database

This is the Image that showing the ‘internal server error’ in ajax success

Please anyone can help
Thanks in Advance!

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Source Url Getting ‘internal Server Error’ in ajax success when already i got the data from database