diff --git a/requirements.txt b/requirements.txt
index 5cbba9f..dd15a02 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,3 @@
 cosl
-ops==2.12.0
+ops==2.13.0
 ops-lib-pgsql
diff --git a/src/charm.py b/src/charm.py
index 8f74370..938ee71 100755
--- a/src/charm.py
+++ b/src/charm.py
@@ -125,7 +125,7 @@ def _get_external_hostname(self) -> str:
         Returns:
             The assigned hostname.
         """
-        hostname = self.config["external_hostname"]
+        hostname = typing.cast(str, self.config["external_hostname"])
         if hostname == "":
             hostname = self.app.name
         return hostname
@@ -459,7 +459,7 @@ def _make_pod_env(self) -> Union[dict, bool, set, str]:
         Returns:
             A dictionary used for envConfig in podspec.
         """
-        env = self.model.config["environment"]
+        env = typing.cast(str, self.model.config["environment"])
 
         if not env:
             return {}