diff --git a/matrix-sdk-android-rx/src/main/java/org/matrix/android/sdk/rx/RxSession.kt b/matrix-sdk-android-rx/src/main/java/org/matrix/android/sdk/rx/RxSession.kt
index cac0a32232..0fe2b01576 100644
--- a/matrix-sdk-android-rx/src/main/java/org/matrix/android/sdk/rx/RxSession.kt
+++ b/matrix-sdk-android-rx/src/main/java/org/matrix/android/sdk/rx/RxSession.kt
@@ -141,8 +141,8 @@ class RxSession(private val session: Session) {
     }
 
     fun getRoomIdByAlias(roomAlias: String,
-                         searchOnServer: Boolean): Single<Optional<RoomAliasDescription>> = singleBuilder {
-        session.getRoomIdByAlias(roomAlias, searchOnServer, it)
+                         searchOnServer: Boolean): Single<Optional<RoomAliasDescription>> = rxSingle {
+        session.getRoomIdByAlias(roomAlias, searchOnServer)
     }
 
     fun getProfileInfo(userId: String): Single<JsonDict> = rxSingle {