public Task<List<BulkmailAnnouncementModel>> GetBulkmailAnnouncementsByPackageTrackingId(string packageTrackingIdentification)
    {
        var announcement = await Context.BulkmailAnnouncement
            .Include(x => x.Tarras)
            .Include(x => x.PackageTrackingIdentifications)
            .Where(x => x.PackageTrackingIdentifications.Any(y => y.Value == packageTrackingIdentification) &&
                        x.AuditReportIndicator != true)
            .FirstAsync();

        return await Context.BulkmailAnnouncement
            .Include(x => x.Tarras)
            .Include(x => x.PackageTrackingIdentifications)
            .Where(x => x.CustomerOrderId == announcement.CustomerOrderId && x.CustomerPartyAccountId == announcement.CustomerPartyAccountId)
            .ToListAsync();
    }

var result = BulkmailAnnouncements.GroupBy(

   // Key: make groups with same "certain properties"
   announcement => new
   {
       CustomerOrderId,
       CustomerPartyAccountId,
   })
   // Result: groups of BulkMailAnnouncements with equal "certain properties"

   // keep only those groups that have at least one BulkMailAnnouncement
   // that has both a true AuditReportIndicator and at least one
   // PackageTrackingIdentification that equals packageTrackingIdentification
   .Where(groupOfBulkMailAnnouncements =>
         groupOfBulkMailAnnouncements.Any(bulkMailAnnouncement =>
            bulkMailAnnouncement.AuditReportIndicator &&
            bulkmailAnnouncment.PackageTrackingIdentifications
                 .Any(packageTrackingId == packageTrakcingIdentification)))

   // from the remaining groups, take the first or default
   .FirstOrDefault(); // or use async version

var announcement = await Context.BulkmailAnnouncement
        .Where(x => x.PackageTrackingIdentifications.Any(y => y.Value == packageTrackingIdentification) &&
                    x.AuditReportIndicator != true)
        .FirstAsync();

var announcement2 = await Context.BulkmailAnnouncement
        .Include(x => x.Tarras)
        .Include(x => x.PackageTrackingIdentifications)
        .Where(x => x.CustomerOrderId == announcement.CustomerOrderId && x.CustomerPartyAccountId == announcement.CustomerPartyAccountId)
        .ToListAsync();

var resultAnnouncement = announcement.Concat(announcement2);
return resultAnnouncement;

return await Context.BulkmailAnnouncement
        .Include(x => x.Tarras)
        .Include(x => x.PackageTrackingIdentifications)
        .Where(x => x.PackageTrackingIdentifications != null
            && x.PackageTrackingIdentifications.Any(y => y.Value == packageTrackingIdentification)
            && x.AuditReportIndicator != true)
        .ToListAsync();

var announcement = await Context.BulkmailAnnouncement
        .Include(x => x.Tarras)
        .Include(x => x.PackageTrackingIdentifications)
        .Where(x => x.PackageTrackingIdentifications != null
            && x.PackageTrackingIdentifications.Any(y => y.Value == packageTrackingIdentification)
            && x.AuditReportIndicator != true)
        .FirstAsync();

return (await Context.BulkmailAnnouncement
    .Include(x => x.Tarras)
    .Include(x => x.PackageTrackingIdentifications)
    .Where(x => x.PackageTrackingIdentifications != null
        && x.PackageTrackingIdentifications.Any(y => y.Value == packageTrackingIdentification)
        && x.AuditReportIndicator != true)
    .GroupBy(x => new { x.CustomerOrderId, x.CustomerPartyAccountId })
.FirstAsync()).ToArray();