diff --git a/src/com/android/settings/fuelgauge/datasaver/DynamicDenylistManager.java b/src/com/android/settings/fuelgauge/datasaver/DynamicDenylistManager.java
index b77d5eb6ddf..ecb2a48fe89 100644
--- a/src/com/android/settings/fuelgauge/datasaver/DynamicDenylistManager.java
+++ b/src/com/android/settings/fuelgauge/datasaver/DynamicDenylistManager.java
@@ -78,6 +78,11 @@ public class DynamicDenylistManager {
             return;
         }
 
+        if (mNetworkPolicyManager == null) {
+            Log.w(TAG, "syncPolicyIfNeeded: invalid mNetworkPolicyManager");
+            return;
+        }
+
         final SharedPreferences.Editor editor = getManualDenylistPref().edit();
         final int[] existedUids = mNetworkPolicyManager
                 .getUidsWithPolicy(POLICY_REJECT_METERED_BACKGROUND);
@@ -91,6 +96,11 @@ public class DynamicDenylistManager {
 
     /** Set policy flags for specific UID. */
     public void setUidPolicyLocked(int uid, int policy) {
+        if (mNetworkPolicyManager == null) {
+            Log.w(TAG, "setUidPolicyLocked: invalid mNetworkPolicyManager");
+            return;
+        }
+
         Log.i(TAG, "setUidPolicyLocked: uid=" + uid + " policy=" + policy);
         synchronized (mLock) {
             mNetworkPolicyManager.setUidPolicy(uid, policy);
@@ -100,7 +110,7 @@ public class DynamicDenylistManager {
 
     /** Suggest a list of package to set as POLICY_REJECT. */
     public void setDenylist(Set<Integer> denylistTargetUids) {
-        if (denylistTargetUids == null) {
+        if (denylistTargetUids == null || mNetworkPolicyManager == null) {
             return;
         }
         final Set<Integer> manualDenylistUids = getDenylistAllUids(getManualDenylistPref());
@@ -164,6 +174,12 @@ public class DynamicDenylistManager {
             Log.w(TAG, "resetDenylistIfNeeded: invalid conditions");
             return;
         }
+
+        if (mNetworkPolicyManager == null) {
+            Log.w(TAG, "setUidPolicyLocked: invalid mNetworkPolicyManager");
+            return;
+        }
+
         synchronized (mLock) {
             final int[] uids = mNetworkPolicyManager
                     .getUidsWithPolicy(POLICY_REJECT_METERED_BACKGROUND);