diff --git a/group_vars/matrix_servers b/group_vars/matrix_servers
index 25fe7895c..27f130d6c 100755
--- a/group_vars/matrix_servers
+++ b/group_vars/matrix_servers
@@ -5240,7 +5240,7 @@ prometheus_nginxlog_exporter_container_labels_traefik_tls_certResolver: "{{ trae
 prometheus_nginxlog_exporter_container_labels_metrics_middleware_basic_auth_enabled: "{{ matrix_metrics_exposure_http_basic_auth_enabled }}"
 prometheus_nginxlog_exporter_container_labels_metrics_middleware_basic_auth_users: "{{ matrix_metrics_exposure_http_basic_auth_users }}"
 
-prometheus_nginxlog_exporter_config_namespaces_matrix_source_tags_auto: |
+prometheus_nginxlog_exporter_config_namespaces_source_tags_auto: |
   {{
     ([matrix_synapse_reverse_proxy_companion_access_log_syslog_integration_tag] if matrix_synapse_reverse_proxy_companion_access_log_syslog_integration_enabled else [])
   }}
diff --git a/roles/custom/matrix_playbook_migration/tasks/validate_config.yml b/roles/custom/matrix_playbook_migration/tasks/validate_config.yml
index 382262d70..dd1c4e8e2 100644
--- a/roles/custom/matrix_playbook_migration/tasks/validate_config.yml
+++ b/roles/custom/matrix_playbook_migration/tasks/validate_config.yml
@@ -103,6 +103,7 @@
     - {'old': 'prometheus_nginxlog_exporter_metrics_proxying_enabled', 'new': 'prometheus_nginxlog_exporter_container_labels_traefik_enabled'}
     - {'old': 'prometheus_nginxlog_exporter_metrics_proxying_hostname', 'new': 'prometheus_nginxlog_exporter_container_labels_traefik_hostname'}
     - {'old': 'prometheus_nginxlog_exporter_metrics_proxying_path_prefix', 'new': 'prometheus_nginxlog_exporter_container_labels_traefik_path_prefix'}
+    - {'old': 'prometheus_nginxlog_exporter_config_namespaces_matrix_source_tags_custom', 'new': 'prometheus_nginxlog_exporter_config_namespaces_source_tags_custom'}
 
 - name: (Deprecation) Catch and report matrix_postgres variables
   ansible.builtin.fail: