diff --git a/packages/google-cloud-spanner/samples/samples/backup_sample_test.py b/packages/google-cloud-spanner/samples/samples/backup_sample_test.py
index 55e7bac1881e..7dfb16589b95 100644
--- a/packages/google-cloud-spanner/samples/samples/backup_sample_test.py
+++ b/packages/google-cloud-spanner/samples/samples/backup_sample_test.py
@@ -135,7 +135,7 @@ def test_copy_backup_with_multiple_kms_keys(
 
 
 @pytest.mark.dependency(depends=["create_backup"])
-@RetryErrors(exception=DeadlineExceeded, max_tries=2)
+@RetryErrors(exception=(DeadlineExceeded, TimeoutError), max_tries=2)
 def test_restore_database(capsys, instance_id, sample_database):
     backup_sample.restore_database(instance_id, RESTORE_DB_ID, BACKUP_ID)
     out, _ = capsys.readouterr()
@@ -145,7 +145,7 @@ def test_restore_database(capsys, instance_id, sample_database):
 
 
 @pytest.mark.dependency(depends=["create_backup_with_encryption_key"])
-@RetryErrors(exception=DeadlineExceeded, max_tries=2)
+@RetryErrors(exception=(DeadlineExceeded, TimeoutError), max_tries=2)
 def test_restore_database_with_encryption_key(
     capsys,
     instance_id,
@@ -164,7 +164,7 @@ def test_restore_database_with_encryption_key(
 
 @pytest.mark.skip(reason="skipped since the KMS keys are not added on test project")
 @pytest.mark.dependency(depends=["create_backup_with_multiple_kms_keys"])
-@RetryErrors(exception=DeadlineExceeded, max_tries=2)
+@RetryErrors(exception=(DeadlineExceeded, TimeoutError), max_tries=2)
 def test_restore_database_with_multiple_kms_keys(
     capsys,
     multi_region_instance_id,
@@ -243,7 +243,7 @@ def test_cancel_backup(capsys, instance_id, sample_database):
     assert cancel_success or cancel_failure
 
 
-@RetryErrors(exception=DeadlineExceeded, max_tries=2)
+@RetryErrors(exception=(DeadlineExceeded, TimeoutError), max_tries=2)
 def test_create_database_with_retention_period(capsys, sample_instance):
     backup_sample.create_database_with_version_retention_period(
         sample_instance.instance_id,
diff --git a/packages/google-cloud-spanner/samples/samples/conftest.py b/packages/google-cloud-spanner/samples/samples/conftest.py
index 83a4d801474a..c6cb9cbb4c4c 100644
--- a/packages/google-cloud-spanner/samples/samples/conftest.py
+++ b/packages/google-cloud-spanner/samples/samples/conftest.py
@@ -79,14 +79,14 @@ def scrub_instance_ignore_not_found(to_scrub):
                 pass
 
         retry_cleanup(to_scrub.delete)()
-    except exceptions.NotFound:
+    except exceptions.GoogleAPICallError:
         pass
 
 
 @pytest.fixture(scope="session")
 def cleanup_old_instances(spanner_client):
-    """Delete instances, created by samples, that are older than an hour."""
-    cutoff = int(time.time()) - 1 * 60 * 60
+    """Delete instances, created by samples, that are older than 4 hours."""
+    cutoff = int(time.time()) - 4 * 60 * 60
     instance_filter = "labels.cloud_spanner_samples:true"
 
     for instance_pb in spanner_client.list_instances(filter_=instance_filter):