ASP.Net Core Entity Framework Error: could not be translated

I have the employee numbers in the database starting stored this way

EmployeeNumber
E123456
E999999
E666666
E111111

I want to write a LINQ statement to match the database EmployeeNumber with employeeId that is passed from web. I wrote the LINQ like this:

_akContext.EmployeeInfos.Where(e => e.EmployeeNumber.TrimStart('E') == employeeId.TrimStart('E')).OrderBy(e => e.EmployeeInfoId).Select(e => e.EmployeeInfoId).ToList();

With the above LINQ statement, I keep getting an error saying:

The LINQ expression 'DbSet<EmployeeInfo>()

.Where(e => e.EmployeeNumber.TrimStart(E) == __TrimStart_0)' could not be translated