diff --git a/dojo/api_v2/serializers.py b/dojo/api_v2/serializers.py
index 4fd5aad7440..34d1129107f 100644
--- a/dojo/api_v2/serializers.py
+++ b/dojo/api_v2/serializers.py
@@ -1158,6 +1158,7 @@ def update(self, instance, validated_data):
         findings_to_remove = set(existing_findings) - set(new_findings)
         findings_to_add = Finding.objects.filter(id__in=[x.id for x in findings_to_add])
         findings_to_remove = Finding.objects.filter(id__in=[x.id for x in findings_to_remove])
+        old_expiration_date = self.instance.expiration_date
         # Make the update in the database
         instance = super().update(instance, validated_data)
         user = getattr(self.context.get("request", None), "user", None)
@@ -1167,6 +1168,9 @@ def update(self, instance, validated_data):
         for finding in findings_to_remove:
             ra_helper.remove_finding_from_risk_acceptance(user, instance, finding)
 
+        if instance.expiration_date != old_expiration_date:
+            ra_helper.reinstate(instance, old_expiration_date)
+
         # Handle orphaned risk acceptances: link to engagement if it now has findings
         # This is fine as Pro has its own model + relationshop to track links with engagements.
         if instance.accepted_findings.exists() and not instance.engagement: