diff --git a/app/src/main/kotlin/com/simplemobiletools/calendar/pro/helpers/DBHelper.kt b/app/src/main/kotlin/com/simplemobiletools/calendar/pro/helpers/DBHelper.kt
index 310e54740..b23bd421d 100644
--- a/app/src/main/kotlin/com/simplemobiletools/calendar/pro/helpers/DBHelper.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/calendar/pro/helpers/DBHelper.kt
@@ -390,7 +390,8 @@ class DBHelper private constructor(val context: Context) : SQLiteOpenHelper(cont
 
         context.updateWidgets()
 
-        ids.forEach {
+        // temporary workaround, will be rewritten in Room
+        ids.filterNot { it == "null" }.forEach {
             context.cancelNotification(it.toLong())
         }