diff --git a/composeApp/src/commonMain/kotlin/com/pixelized/desktop/lwa/repository/alteration/AlterationStore.kt b/composeApp/src/commonMain/kotlin/com/pixelized/desktop/lwa/repository/alteration/AlterationStore.kt
index 708f579..7af774f 100644
--- a/composeApp/src/commonMain/kotlin/com/pixelized/desktop/lwa/repository/alteration/AlterationStore.kt
+++ b/composeApp/src/commonMain/kotlin/com/pixelized/desktop/lwa/repository/alteration/AlterationStore.kt
@@ -5,6 +5,7 @@ import com.pixelized.desktop.lwa.repository.network.NetworkRepository
 import com.pixelized.shared.lwa.model.alteration.Alteration
 import com.pixelized.shared.lwa.model.alteration.AlterationJsonFactory
 import com.pixelized.shared.lwa.protocol.websocket.ApiSynchronisation
+import com.pixelized.shared.lwa.protocol.websocket.ApiSynchronisation.AlterationApiSynchronisation
 import com.pixelized.shared.lwa.protocol.websocket.SocketMessage
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
@@ -118,13 +119,15 @@ class AlterationStore(
 
     private suspend fun handleMessage(message: SocketMessage) {
         when (message) {
-            is ApiSynchronisation.AlterationUpdate -> updateAlterationFlow(
-                alterationId = message.alterationId,
-            )
+            is AlterationApiSynchronisation -> when (message) {
+                is ApiSynchronisation.AlterationDelete -> updateAlterationFlow(
+                    alterationId = message.alterationId,
+                )
 
-            is ApiSynchronisation.AlterationDelete -> _alterationsFlow.update { alterations ->
-                alterations.toMutableMap().also {
-                    it.remove(message.alterationId)
+                is ApiSynchronisation.AlterationUpdate -> _alterationsFlow.update { alterations ->
+                    alterations.toMutableMap().also {
+                        it.remove(message.alterationId)
+                    }
                 }
             }
 
diff --git a/composeApp/src/commonMain/kotlin/com/pixelized/desktop/lwa/repository/characterSheet/CharacterSheetStore.kt b/composeApp/src/commonMain/kotlin/com/pixelized/desktop/lwa/repository/characterSheet/CharacterSheetStore.kt
index 2877ffb..1bcedce 100644
--- a/composeApp/src/commonMain/kotlin/com/pixelized/desktop/lwa/repository/characterSheet/CharacterSheetStore.kt
+++ b/composeApp/src/commonMain/kotlin/com/pixelized/desktop/lwa/repository/characterSheet/CharacterSheetStore.kt
@@ -195,27 +195,31 @@ class CharacterSheetStore(
         _detailFlow.update(character)
     }
 
-    private suspend fun updateAlterations(
+    private fun updateAlterations(
         characterSheetId: String,
         alterationId: String,
         active: Boolean,
     ) {
-        if (alterationStore.alteration(alterationId = alterationId) == null) return
-        val sheet = getCharacterSheet(characterSheetId = characterSheetId)
-
+        // check if the alteration exist
+        alterationStore.alteration(alterationId = alterationId) ?: return
+        // check if the character exit (detail may have not been downloaded)
+        val sheet = detailFlow.value[characterSheetId] ?: return
+        // check if the alteration is already active or not on this character.
         val containAlteration = sheet.alterations.contains(alterationId)
 
         if (containAlteration.not() && active) {
-            val alterations = sheet.alterations.toMutableList().also {
-                it.add(alterationId)
-            }
-            _detailFlow.update(sheet.copy(alterations = alterations))
+            _detailFlow.update(
+                sheet = sheet.copy(
+                    alterations = sheet.alterations.toMutableList().also { it.add(alterationId) }
+                )
+            )
         }
         if (containAlteration && active.not()) {
-            val alterations = sheet.alterations.toMutableList().also {
-                it.remove(alterationId)
-            }
-            _detailFlow.update(sheet.copy(alterations = alterations))
+            _detailFlow.update(
+                sheet = sheet.copy(
+                    alterations = sheet.alterations.toMutableList().also { it.remove(alterationId) }
+                )
+            )
         }
     }