diff --git a/app/src/main/java/eu/kanade/tachiyomi/data/preference/PreferencesHelper.kt b/app/src/main/java/eu/kanade/tachiyomi/data/preference/PreferencesHelper.kt
index 1824968f05..87975c25fd 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/data/preference/PreferencesHelper.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/data/preference/PreferencesHelper.kt
@@ -116,7 +116,7 @@ class PreferencesHelper(val context: Context) {
 
     fun clear() = prefs.edit().clear().apply()
 
-    fun oldTheme() = prefs.getInt(Keys.theme, 5)
+    fun oldTheme() = flowPrefs.getInt(Keys.theme, 5)
 
     fun nightMode() = flowPrefs.getInt(Keys.nightMode, AppCompatDelegate.MODE_NIGHT_FOLLOW_SYSTEM)
 
diff --git a/app/src/main/java/eu/kanade/tachiyomi/util/system/ThemeUtil.kt b/app/src/main/java/eu/kanade/tachiyomi/util/system/ThemeUtil.kt
index 0da1946ca4..cc952841b9 100644
--- a/app/src/main/java/eu/kanade/tachiyomi/util/system/ThemeUtil.kt
+++ b/app/src/main/java/eu/kanade/tachiyomi/util/system/ThemeUtil.kt
@@ -87,8 +87,9 @@ object ThemeUtil {
 }
 
 fun AppCompatActivity.setThemeAndNight(preferences: PreferencesHelper) {
-    if (preferences.nightMode().isNotSet()) {
-        ThemeUtil.convertTheme(preferences, preferences.oldTheme())
+    if (preferences.nightMode().isNotSet() && preferences.oldTheme().isSet()) {
+        ThemeUtil.convertTheme(preferences, preferences.oldTheme().get())
+        preferences.oldTheme().delete()
     }
     if (AppCompatDelegate.getDefaultNightMode() != preferences.nightMode().get()) {
         AppCompatDelegate.setDefaultNightMode(preferences.nightMode().get())