diff --git a/services/companion/java/com/android/server/companion/AssociationStoreImpl.java b/services/companion/java/com/android/server/companion/AssociationStoreImpl.java
index cb28254f70db6..bd2a97df1d7a6 100644
--- a/services/companion/java/com/android/server/companion/AssociationStoreImpl.java
+++ b/services/companion/java/com/android/server/companion/AssociationStoreImpl.java
@@ -23,6 +23,7 @@ import android.annotation.UserIdInt;
 import android.companion.AssociationInfo;
 import android.net.MacAddress;
 import android.util.Log;
+import android.util.Slog;
 import android.util.SparseArray;
 
 import com.android.internal.annotations.GuardedBy;
@@ -80,7 +81,7 @@ class AssociationStoreImpl implements AssociationStore {
 
         synchronized (mLock) {
             if (mIdMap.containsKey(id)) {
-                if (DEBUG) Log.w(TAG, "Association already stored.");
+                Slog.e(TAG, "Association with id " + id + " already exists.");
                 return;
             }
             mIdMap.put(id, association);
diff --git a/services/companion/java/com/android/server/companion/CompanionDeviceManagerService.java b/services/companion/java/com/android/server/companion/CompanionDeviceManagerService.java
index 13a5a28299458..02a0a95791233 100644
--- a/services/companion/java/com/android/server/companion/CompanionDeviceManagerService.java
+++ b/services/companion/java/com/android/server/companion/CompanionDeviceManagerService.java
@@ -813,7 +813,13 @@ public class CompanionDeviceManagerService extends SystemService {
         synchronized (mPreviouslyUsedIds) {
             // First: collect all IDs currently in use for this user's Associations.
             final SparseBooleanArray usedIds = new SparseBooleanArray();
-            for (AssociationInfo it : mAssociationStore.getAssociationsForUser(userId)) {
+
+            // We should really only be checking associations for the given user (i.e.:
+            // mAssociationStore.getAssociationsForUser(userId)), BUT in the past we've got in a
+            // state where association IDs were not assigned correctly in regard to
+            // user-to-association-ids-range (e.g. associations with IDs from 1 to 100,000 should
+            // always belong to u0), so let's check all the associations.
+            for (AssociationInfo it : mAssociationStore.getAssociations()) {
                 usedIds.put(it.getId(), true);
             }
 
diff --git a/services/companion/java/com/android/server/companion/PersistentDataStore.java b/services/companion/java/com/android/server/companion/PersistentDataStore.java
index d0cc12286b128..36393894f7277 100644
--- a/services/companion/java/com/android/server/companion/PersistentDataStore.java
+++ b/services/companion/java/com/android/server/companion/PersistentDataStore.java
@@ -25,6 +25,8 @@ import static com.android.internal.util.XmlUtils.writeBooleanAttribute;
 import static com.android.internal.util.XmlUtils.writeIntAttribute;
 import static com.android.internal.util.XmlUtils.writeLongAttribute;
 import static com.android.internal.util.XmlUtils.writeStringAttribute;
+import static com.android.server.companion.CompanionDeviceManagerService.getFirstAssociationIdForUser;
+import static com.android.server.companion.CompanionDeviceManagerService.getLastAssociationIdForUser;
 import static com.android.server.companion.DataStoreUtils.createStorageFileForUser;
 import static com.android.server.companion.DataStoreUtils.isEndOfTag;
 import static com.android.server.companion.DataStoreUtils.isStartOfTag;
@@ -194,7 +196,25 @@ final class PersistentDataStore {
 
             // Associations for all users are stored in a single "flat" set: so we read directly
             // into it.
-            readStateForUser(userId, allAssociationsOut, previouslyUsedIds);
+            final Set<AssociationInfo> associationsForUser = new HashSet<>();
+            readStateForUser(userId, associationsForUser, previouslyUsedIds);
+
+            // Go through all the associations for the user and check if their IDs are within
+            // the allowed range (for the user).
+            final int firstAllowedId = getFirstAssociationIdForUser(userId);
+            final int lastAllowedId = getLastAssociationIdForUser(userId);
+            for (AssociationInfo association : associationsForUser) {
+                final int id = association.getId();
+                if (id < firstAllowedId || id > lastAllowedId) {
+                    Slog.e(TAG, "Wrong association ID assignment: " + id + ". "
+                            + "Association belongs to u" + userId + " and thus its ID should be "
+                            + "within [" + firstAllowedId + ", " + lastAllowedId + "] range.");
+                    // TODO(b/224736262): try fixing (re-assigning) the ID?
+                }
+            }
+
+            // Add user's association to the "output" set.
+            allAssociationsOut.addAll(associationsForUser);
 
             // Save previously used IDs for this user into the "out" structure.
             previouslyUsedIdsPerUserOut.append(userId, previouslyUsedIds);
@@ -369,7 +389,7 @@ final class PersistentDataStore {
         // existing ones from the backup files. And the fact that we are reading from a V0 file,
         // means that CDM hasn't assigned any IDs yet, so we can just start from the first available
         // id for each user (eg. 1 for user 0; 100 001 - for user 1; 200 001 - for user 2; etc).
-        int associationId = CompanionDeviceManagerService.getFirstAssociationIdForUser(userId);
+        int associationId = getFirstAssociationIdForUser(userId);
         while (true) {
             parser.nextTag();
             if (isEndOfTag(parser, XML_TAG_ASSOCIATIONS)) break;