C#

Hello, I am using the below code to fetch some data from database and getting the error "Sequence contains no elements"

 public static IEnumerable<CompanyLicenseKey> GetCompanyLicenseKey()
{
            OPEntities onepassDB = new OPEntities();

            //Let's get the onepass User model first
            var user = onepassDB.UserAccounts.Where(x => x.Email == OnePassUserAccountEmail).First(); //error in this line

            var userLicenseList = from c in user.CompanyProfiles
                                  join l in onepassDB.CompanyLicenseKeys.Where(x => x.IsDisabled == false)
                                  .Select(x => new { x.CRMID, x.LicenseKey, x.FriendlyName, x.ProductName })
                                  on new { c.CRMID } equals new { l.CRMID }
                                  select new Models.OnePass.CompanyLicenseKey { LicenseKey = l.LicenseKey, FriendlyName = l.FriendlyName, ProductName = l.ProductName };

            if (ProductName == "")
                return userLicenseList.ToList().OrderBy(x => x.FriendlyName);
            else
                return userLicenseList.Where(x => x.ProductName == ProductName).ToList().OrderBy(x => x.FriendlyName);
        }

Error image

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