diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/room/model/RoomGuestAccessContent.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/room/model/RoomGuestAccessContent.kt
index 99b035d30e..8eea0d3d06 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/room/model/RoomGuestAccessContent.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/room/model/RoomGuestAccessContent.kt
@@ -18,6 +18,7 @@ package org.matrix.android.sdk.api.session.room.model
 
 import com.squareup.moshi.Json
 import com.squareup.moshi.JsonClass
+import timber.log.Timber
 
 /**
  * Class representing the EventType.STATE_ROOM_GUEST_ACCESS state event content
@@ -26,8 +27,17 @@ import com.squareup.moshi.JsonClass
 @JsonClass(generateAdapter = true)
 data class RoomGuestAccessContent(
         // Required. Whether guests can join the room. One of: ["can_join", "forbidden"]
-        @Json(name = "guest_access") val guestAccess: GuestAccess? = null
-)
+        @Json(name = "guest_access") private val _guestAccess: String? = null
+) {
+    val guestAccess: GuestAccess? = when (_guestAccess) {
+        "can_join"  -> GuestAccess.CanJoin
+        "forbidden" -> GuestAccess.Forbidden
+        else        -> {
+            Timber.w("Invalid value for GuestAccess: `$_guestAccess`")
+            null
+        }
+    }
+}
 
 @JsonClass(generateAdapter = false)
 enum class GuestAccess(val value: String) {
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/state/DefaultStateService.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/state/DefaultStateService.kt
index f2640fd1e7..3c42b77ae8 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/state/DefaultStateService.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/state/DefaultStateService.kt
@@ -138,7 +138,7 @@ internal class DefaultStateService @AssistedInject constructor(@Assisted private
         if (guestAccess != null) {
             sendStateEvent(
                     eventType = EventType.STATE_ROOM_GUEST_ACCESS,
-                    body = RoomGuestAccessContent(guestAccess).toContent(),
+                    body = mapOf("guest_access" to guestAccess),
                     stateKey = null
             )
         }