Otp Verification with in 5 minutes

I need to check the otp generated time. When user entered otp it will expire with in 5 minutes. I need a query in entity framework or linuq

 

I wirte like below but i am not getting result, I thought it wrong can any help me

 

 

 

query

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var login = _context.MobileOtp.FirstOrDefault(i => i.MobileNumber == mobileNumber && (i.CreateDate.Minute - DateTime.Now.Minute) <= 5 && i.Otp == otp); 

 

 

Please ASAP