diff --git a/app/models/case_log.rb b/app/models/case_log.rb
index 6b3950c6e..0ff5e9c95 100644
--- a/app/models/case_log.rb
+++ b/app/models/case_log.rb
@@ -186,6 +186,10 @@ private
       dynamically_not_required << "net_income_frequency"
     end
 
+    if tenancy_type == "Fixed term – Secure"
+      dynamically_not_required << "fixed_term_tenancy"
+    end
+
     required.delete_if { |key, _value| dynamically_not_required.include?(key) }
   end
 end
diff --git a/docs/api/DLUHC-CORE-Data.v1.json b/docs/api/DLUHC-CORE-Data.v1.json
index f50e096fb..64d5ca517 100644
--- a/docs/api/DLUHC-CORE-Data.v1.json
+++ b/docs/api/DLUHC-CORE-Data.v1.json
@@ -873,7 +873,8 @@
           },
           "fixed_term_tenancy": {
             "type": "string",
-            "minLength": 1
+            "minLength": 1,
+            "pattern": "((?!1|0)([0-9][0-9]))+"
           },
           "tenancy_type": {
             "type": "string",