if you need to include Date in your where condition then send date as parameter DeleteEmployeeStatus method and update the method signature
_service.DeleteEmployeeStatus(sectorId, dt);
then you need both conditions like
where a.SectorID == sectorId and a.ToDate = dt
but when you are working with
DateTime
value with Database
Date/DateTime
in entity framework you need to be careful with the code. Read below article for few ways you can try
LINQ query to compare only date part of DateTime[
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