diff --git a/rhodecode/model/db.py b/rhodecode/model/db.py
--- a/rhodecode/model/db.py
+++ b/rhodecode/model/db.py
@@ -3834,7 +3834,7 @@ class ChangesetComment(Base, BaseModel):
         return q.all()
 
     @classmethod
-    def get_index_from_version(cls, pr_version, versions=None, num_versions=None):
+    def get_index_from_version(cls, pr_version, versions=None, num_versions=None) -> int:
         if pr_version is None:
             return 0
 
@@ -3845,7 +3845,7 @@ class ChangesetComment(Base, BaseModel):
         try:
             return num_versions.index(pr_version) + 1
         except (IndexError, ValueError):
-            return
+            return 0
 
     @property
     def outdated(self):