fix

Author: rustagir

source/whats-new.txt

@@ -29,7 +29,7 @@ Learn what's new in:
 * :ref:`Version 2.28 <csharp-version-2.28>`
 * :ref:`Version 2.27 <csharp-version-2.27>`
 * :ref:`Version 2.26 <csharp-version-2.26>`
-* :ref:`Version 2.25 <version-2.25>`
+* :ref:`Version 2.25 <csharp-version-2.25>`
 
 .. _upcoming-breaking-changes:
 
@@ -406,6 +406,7 @@ The 2.26 driver release includes the following new features:
 - Implemented read and write retries to other ``mongos`` instances when
   possible.
 
+.. _csharp-version-2.25:
 .. _version-2.25:
 
 What's New in 2.25