diff --git a/lib/charms/tls_certificates_interface/v2/tls_certificates.py b/lib/charms/tls_certificates_interface/v2/tls_certificates.py
index 469386a..99741f5 100644
--- a/lib/charms/tls_certificates_interface/v2/tls_certificates.py
+++ b/lib/charms/tls_certificates_interface/v2/tls_certificates.py
@@ -1349,8 +1349,7 @@ def certificate_issued_for_csr(
         Args:
             app_name (str): Application name that the CSR belongs to.
             csr (str): Certificate Signing Request.
-            relation_id (int): Relation ID
-
+            relation_id (Optional[int]): Relation ID
         Returns:
             bool: True/False depending on whether a certificate has been issued for the given CSR.
         """