diff --git a/prowler/providers/m365/models.py b/prowler/providers/m365/models.py
index f77bc8ee4c..ca9d74c44d 100644
--- a/prowler/providers/m365/models.py
+++ b/prowler/providers/m365/models.py
@@ -1,3 +1,5 @@
+from typing import Optional
+
 from pydantic import BaseModel
 
 from prowler.config.config import output_file_timestamp
@@ -16,7 +18,7 @@ class M365IdentityInfo(BaseModel):
 
 class M365RegionConfig(BaseModel):
     name: str = ""
-    authority: str = None
+    authority: Optional[str] = None
     base_url: str = ""
     credential_scopes: list = []