diff --git a/model/jpa/src/main/java/org/keycloak/models/jpa/session/JpaUserSessionPersisterProvider.java b/model/jpa/src/main/java/org/keycloak/models/jpa/session/JpaUserSessionPersisterProvider.java
index 685b975d2e..0182b25d0b 100644
--- a/model/jpa/src/main/java/org/keycloak/models/jpa/session/JpaUserSessionPersisterProvider.java
+++ b/model/jpa/src/main/java/org/keycloak/models/jpa/session/JpaUserSessionPersisterProvider.java
@@ -90,25 +90,43 @@ public class JpaUserSessionPersisterProvider implements UserSessionPersisterProv
         PersistentAuthenticatedClientSessionAdapter adapter = new PersistentAuthenticatedClientSessionAdapter(session, clientSession);
         PersistentClientSessionModel model = adapter.getUpdatedModel();
 
-        PersistentClientSessionEntity entity = new PersistentClientSessionEntity();
+        String userSessionId = clientSession.getUserSession().getId();
+        String clientId;
+        String clientStorageProvider;
+        String externalClientId;
         StorageId clientStorageId = new StorageId(clientSession.getClient().getId());
         if (clientStorageId.isLocal()) {
-            entity.setClientId(clientStorageId.getId());
-            entity.setClientStorageProvider(PersistentClientSessionEntity.LOCAL);
-            entity.setExternalClientId(PersistentClientSessionEntity.LOCAL);
-
+            clientId = clientStorageId.getId();
+            clientStorageProvider = PersistentClientSessionEntity.LOCAL;
+            externalClientId = PersistentClientSessionEntity.LOCAL;
         } else {
-            entity.setClientId(PersistentClientSessionEntity.EXTERNAL);
-            entity.setClientStorageProvider(clientStorageId.getProviderId());
-            entity.setExternalClientId(clientStorageId.getExternalId());
+            clientId = PersistentClientSessionEntity.EXTERNAL;
+            clientStorageProvider = clientStorageId.getProviderId();
+            externalClientId = clientStorageId.getExternalId();
         }
-        entity.setTimestamp(clientSession.getTimestamp());
         String offlineStr = offlineToString(offline);
-        entity.setOffline(offlineStr);
-        entity.setUserSessionId(clientSession.getUserSession().getId());
+        boolean exists = false;
+
+        PersistentClientSessionEntity entity = em.find(PersistentClientSessionEntity.class, new PersistentClientSessionEntity.Key(userSessionId, clientId, clientStorageProvider, externalClientId, offlineStr));
+        if (entity != null) {
+            // client session can already exist in some circumstances (EG. in case it was already present, but expired in the infinispan, but not yet expired in the DB)
+            exists = true;
+        } else {
+            entity = new PersistentClientSessionEntity();
+            entity.setUserSessionId(userSessionId);
+            entity.setClientId(clientId);
+            entity.setClientStorageProvider(clientStorageProvider);
+            entity.setExternalClientId(externalClientId);
+            entity.setOffline(offlineStr);
+        }
+
+        entity.setTimestamp(clientSession.getTimestamp());
         entity.setData(model.getData());
-        em.persist(entity);
-        em.flush();
+
+        if (!exists) {
+            em.persist(entity);
+            em.flush();
+        }
     }
 
     @Override
diff --git a/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/oauth/OfflineTokenTest.java b/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/oauth/OfflineTokenTest.java
index 6a22a816a7..6f27b5b753 100755
--- a/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/oauth/OfflineTokenTest.java
+++ b/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/oauth/OfflineTokenTest.java
@@ -57,6 +57,7 @@ import org.keycloak.testsuite.arquillian.annotation.DisableFeature;
 import org.keycloak.testsuite.auth.page.AuthRealm;
 import org.keycloak.testsuite.pages.AccountApplicationsPage;
 import org.keycloak.testsuite.pages.LoginPage;
+import org.keycloak.testsuite.updaters.RealmAttributeUpdater;
 import org.keycloak.testsuite.util.ClientBuilder;
 import org.keycloak.testsuite.util.ClientManager;
 import org.keycloak.testsuite.util.OAuthClient;
@@ -743,6 +744,64 @@ public class OfflineTokenTest extends AbstractKeycloakTest {
         testOfflineSessionExpiration(IDLE_LIFESPAN, MAX_LIFESPAN, IDLE_LIFESPAN + SessionTimeoutHelper.IDLE_TIMEOUT_WINDOW_SECONDS + 60);
     }
 
+    // Issue 13706
+    @Test
+    public void offlineTokenReauthenticationWhenOfflinClientSessionExpired() throws Exception {
+        // expect that offline session expired by idle timeout
+        final int MAX_LIFESPAN = 360000;
+        final int IDLE_LIFESPAN = 900;
+
+        getTestingClient().testing().setTestingInfinispanTimeService();
+
+        int prev[] = null;
+        try (RealmAttributeUpdater rau = new RealmAttributeUpdater(adminClient.realm("test")).setSsoSessionIdleTimeout(900).update()) {
+            // Step 1 - offline login with "offline-client"
+            prev = changeOfflineSessionSettings(true, MAX_LIFESPAN, IDLE_LIFESPAN);
+
+            oauth.scope(OAuth2Constants.OFFLINE_ACCESS);
+            oauth.clientId("offline-client");
+            oauth.redirectUri(offlineClientAppUri);
+
+            oauth.doLogin("test-user@localhost", "password");
+            String code = oauth.getCurrentQuery().get(OAuth2Constants.CODE);
+            OAuthClient.AccessTokenResponse tokenResponse = oauth.doAccessTokenRequest(code, "secret1");
+            assertOfflineToken(tokenResponse);
+
+            // Step 2 - set some offset to refresh SSO session and offline user session. But use different client, so that we don't refresh offlineClientSession of client "offline-client"
+            setTimeOffset(800);
+            oauth.clientId("test-app");
+            oauth.redirectUri(APP_ROOT + "/auth");
+            oauth.openLoginForm();
+
+            code = oauth.getCurrentQuery().get(OAuth2Constants.CODE);
+            tokenResponse = oauth.doAccessTokenRequest(code, "password");
+            assertOfflineToken(tokenResponse);
+
+            // Step 3 - set bigger time offset and login with the original client "offline-token". Login should be successful and offline client session for "offline-client" should be re-created now
+            setTimeOffset(900 + SessionTimeoutHelper.PERIODIC_CLEANER_IDLE_TIMEOUT_WINDOW_SECONDS + 20);
+            oauth.clientId("offline-client");
+            oauth.redirectUri(offlineClientAppUri);
+            oauth.openLoginForm();
+
+            code = oauth.getCurrentQuery().get(OAuth2Constants.CODE);
+            tokenResponse = oauth.doAccessTokenRequest(code, "secret1");
+            assertOfflineToken(tokenResponse);
+
+        } finally {
+            getTestingClient().testing().revertTestingInfinispanTimeService();
+            changeOfflineSessionSettings(false, prev[0], prev[1]);
+        }
+    }
+
+    // Asserts that refresh token in the tokenResponse is offlineToken. Return parsed offline token
+    private RefreshToken assertOfflineToken(OAuthClient.AccessTokenResponse tokenResponse) {
+        Assert.assertEquals(200, tokenResponse.getStatusCode());
+        String offlineTokenString = tokenResponse.getRefreshToken();
+        RefreshToken offlineToken = oauth.parseRefreshToken(offlineTokenString);
+        assertEquals(TokenUtil.TOKEN_TYPE_OFFLINE, offlineToken.getType());
+        return offlineToken;
+    }
+
     @Test
     public void offlineTokenRequest_ClientES256_RealmPS256() throws Exception {
         conductOfflineTokenRequest(Algorithm.HS256, Algorithm.ES256, Algorithm.PS256);