diff --git a/app/gosqs/delete_message_batch.go b/app/gosqs/delete_message_batch.go
index 9c0a223..64af928 100644
--- a/app/gosqs/delete_message_batch.go
+++ b/app/gosqs/delete_message_batch.go
@@ -68,13 +68,19 @@ func DeleteMessageBatchV1(req *http.Request) (int, interfaces.AbstractResponseBo
 	}
 	defer queue.UnlockMu()
 
-	deleteMessageMap := make(map[string]*deleteEntry)
+	// Ключ — Id, а НЕ ReceiptHandle: два entry с одинаковым ReceiptHandle и разными
+	// Id не должны перезаписывать друг друга (первый исчезал бы и не попадал ни в
+	// Successful, ни в Failed — ревью 2026-10-11). entriesByHandle — обратный индекс.
+	entriesByID := make(map[string]*deleteEntry)
+	entriesByHandle := make(map[string][]*deleteEntry)
 	for _, entry := range requestBody.Entries {
-		deleteMessageMap[entry.ReceiptHandle] = &deleteEntry{
+		de := &deleteEntry{
 			Id:            entry.Id,
 			ReceiptHandle: entry.ReceiptHandle,
 			Deleted:       false,
 		}
+		entriesByID[entry.Id] = de
+		entriesByHandle[entry.ReceiptHandle] = append(entriesByHandle[entry.ReceiptHandle], de)
 	}
 
 	deletedEntries := make([]models.DeleteMessageBatchResultEntry, 0)
@@ -87,7 +93,7 @@ func DeleteMessageBatchV1(req *http.Request) (int, interfaces.AbstractResponseBo
 			continue
 		}
 		message := &queue.Messages[i]
-		de, found := deleteMessageMap[message.ReceiptHandle]
+		des, found := entriesByHandle[message.ReceiptHandle]
 		if !found {
 			continue
 		}
@@ -97,8 +103,10 @@ func DeleteMessageBatchV1(req *http.Request) (int, interfaces.AbstractResponseBo
 		queue.ClearInFlight(i, message.ReceiptHandle)
 		queue.UnlockGroup(groupID)
 		// Duplicates НЕ чистим — dedup-окно 5 минут живёт независимо от удаления (AWS).
-		de.Deleted = true
-		deletedEntries = append(deletedEntries, models.DeleteMessageBatchResultEntry{Id: de.Id})
+		for _, de := range des {
+			de.Deleted = true
+			deletedEntries = append(deletedEntries, models.DeleteMessageBatchResultEntry{Id: de.Id})
+		}
 		deletedUuids = append(deletedUuids, uuid)
 		queue.RemoveIndex(i)
 	}
@@ -108,7 +116,7 @@ func DeleteMessageBatchV1(req *http.Request) (int, interfaces.AbstractResponseBo
 	persistence.SaveQueue(key, queue)
 
 	notFoundEntries := make([]models.BatchResultErrorEntry, 0)
-	for _, de := range deleteMessageMap {
+	for _, de := range entriesByID {
 		if !de.Deleted {
 			notFoundEntries = append(notFoundEntries, models.BatchResultErrorEntry{
 				Code:        "1",
diff --git a/app/gosqs/send_message.go b/app/gosqs/send_message.go
index d9fb63b..77071c6 100644
--- a/app/gosqs/send_message.go
+++ b/app/gosqs/send_message.go
@@ -117,6 +117,9 @@ func SendMessageV1(req *http.Request) (int, interfaces.AbstractResponseBody) {
 		return utils.CreateErrorResponseV1("OverLimit", true)
 	}
 
+	if requestBody.DelaySeconds < 0 || requestBody.DelaySeconds > 900 {
+		return utils.CreateErrorResponseV1("InvalidParameterValue", true)
+	}
 	if requestBody.DelaySeconds != 0 {
 		delaySecs = requestBody.DelaySeconds
 	}