diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/timeline/Timeline.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/timeline/Timeline.kt
index eb4a9b59e4..d7d6682046 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/timeline/Timeline.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/timeline/Timeline.kt
@@ -104,6 +104,7 @@ interface Timeline {
     interface Listener {
         /**
          * Call when the timeline has been updated through pagination or sync.
+         * The latest event is the first in the list
          * @param snapshot the most up to date snapshot
          */
         fun onTimelineUpdated(snapshot: List<TimelineEvent>)
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/store/IMXCryptoStore.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/store/IMXCryptoStore.kt
index a8f65e9219..c5a89b10e7 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/store/IMXCryptoStore.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/store/IMXCryptoStore.kt
@@ -262,7 +262,7 @@ internal interface IMXCryptoStore {
      * @param deviceKey the public key of the other device.
      * @return The Base64 end-to-end session, or null if not found
      */
-    fun getDeviceSession(sessionId: String?, deviceKey: String?): OlmSessionWrapper?
+    fun getDeviceSession(sessionId: String, deviceKey: String): OlmSessionWrapper?
 
     /**
      * Retrieve the last used sessionId, regarding `lastReceivedMessageTs`, or null if no session exist
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/store/db/RealmCryptoStore.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/store/db/RealmCryptoStore.kt
index bd51cf8539..a6f3f5d593 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/store/db/RealmCryptoStore.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/store/db/RealmCryptoStore.kt
@@ -555,11 +555,7 @@ internal class RealmCryptoStore @Inject constructor(
         }
     }
 
-    override fun getDeviceSession(sessionId: String?, deviceKey: String?): OlmSessionWrapper? {
-        if (sessionId == null || deviceKey == null) {
-            return null
-        }
-
+    override fun getDeviceSession(sessionId: String, deviceKey: String): OlmSessionWrapper? {
         val key = OlmSessionEntity.createPrimaryKey(sessionId, deviceKey)
 
         // If not in cache (or not found), try to read it from realm