Adds docs.

docs/guides/troubleshoot-tls-certificates.md

@@ -0,0 +1,24 @@
+# Troubleshoot TLS Certificates
+
+If services show invalid certificates:
+
+1. Check certificate status:
+   ```bash
+   kubectl get certificates -A
+   ```
+
+2. Examine certificate details:
+   ```bash
+   kubectl describe certificate <cert-name> -n <namespace>
+   ```
+
+3. Check for cert-manager issues:
+   ```bash
+   kubectl get pods -n cert-manager
+   kubectl logs -l app=cert-manager -n cert-manager
+   ```
+
+4. Verify the Cloudflare API token is correctly set up:
+   ```bash
+   kubectl get secret cloudflare-api-token -n internal
+   ```