diff --git a/src/com/android/settings/wifi/calling/WifiCallingSettingsForSub.java b/src/com/android/settings/wifi/calling/WifiCallingSettingsForSub.java
index 76b5c7ae8a4..ae233a5b58d 100644
--- a/src/com/android/settings/wifi/calling/WifiCallingSettingsForSub.java
+++ b/src/com/android/settings/wifi/calling/WifiCallingSettingsForSub.java
@@ -112,7 +112,8 @@ public class WifiCallingSettingsForSub extends SettingsPreferenceFragment
             final CarrierConfigManager configManager = (CarrierConfigManager)
                     activity.getSystemService(Context.CARRIER_CONFIG_SERVICE);
             if (configManager != null) {
-                PersistableBundle b = configManager.getConfigForSubId(mSubId);
+                PersistableBundle b =
+                        configManager.getConfigForSubId(WifiCallingSettingsForSub.this.mSubId);
                 if (b != null) {
                     isWfcModeEditable = b.getBoolean(
                             CarrierConfigManager.KEY_EDITABLE_WFC_MODE_BOOL);