Hi @Roy Sharma ,
Welcome to Q&A forum!
According to my research and testing, I found that functions that return multi-cell ranges or arrays will be prefixed with @ if Array formulas were authored in an older version of Excel.
This is the default design of Excel 365, It is recommended that you go to File>Feedback in Excel to submit your feedback on this issue.
For more information about the @ operator, please refer to: Implicit intersection operator: @.
Any updates, please let me know.
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