diff --git a/libsignal-service/src/main/java/org/whispersystems/signalservice/api/SignalServiceMessageSender.java b/libsignal-service/src/main/java/org/whispersystems/signalservice/api/SignalServiceMessageSender.java
index a082752d9e..e5a46c2b30 100644
--- a/libsignal-service/src/main/java/org/whispersystems/signalservice/api/SignalServiceMessageSender.java
+++ b/libsignal-service/src/main/java/org/whispersystems/signalservice/api/SignalServiceMessageSender.java
@@ -2114,10 +2114,12 @@ public class SignalServiceMessageSender {
     }
 
     for (int i = 0; i < RETRY_COUNT; i++) {
-      GroupTargetInfo            targetInfo     = buildGroupTargetInfo(recipients);
+            GroupTargetInfo targetInfo         = buildGroupTargetInfo(recipients);
+      final GroupTargetInfo targetInfoSnapshot = targetInfo;
+
       Set<SignalProtocolAddress> sharedWith     = aciStore.getSenderKeySharedWith(distributionId);
       List<SignalServiceAddress> needsSenderKey = targetInfo.destinations.stream()
-                                                                         .filter(a -> !sharedWith.contains(a))
+                                                                         .filter(a -> !sharedWith.contains(a) || targetInfoSnapshot.sessions.get(a) == null)
                                                                          .map(a -> ServiceId.parseOrThrow(a.getName()))
                                                                          .distinct()
                                                                          .map(SignalServiceAddress::new)
diff --git a/libsignal-service/src/main/java/org/whispersystems/signalservice/api/crypto/SignalSealedSessionCipher.java b/libsignal-service/src/main/java/org/whispersystems/signalservice/api/crypto/SignalSealedSessionCipher.java
index adbef7558e..8259872d7a 100644
--- a/libsignal-service/src/main/java/org/whispersystems/signalservice/api/crypto/SignalSealedSessionCipher.java
+++ b/libsignal-service/src/main/java/org/whispersystems/signalservice/api/crypto/SignalSealedSessionCipher.java
@@ -56,6 +56,11 @@ public class SignalSealedSessionCipher {
   {
     try (SignalSessionLock.Lock unused = lock.acquire()) {
       List<SessionRecord> recipientSessions = recipients.stream().map(sessionMap::get).collect(Collectors.toList());
+
+      if (recipientSessions.contains(null)) {
+        throw new NoSessionException("No session for some recipients");
+      }
+
       return cipher.multiRecipientEncrypt(recipients, recipientSessions, content);
     }
   }