diff --git a/VERSION b/VERSION
index 6244a82a..3233802f 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.18.0-develop25
+1.18.0-develop26
diff --git a/modules/meta.py b/modules/meta.py
index 07f98407..855fc372 100644
--- a/modules/meta.py
+++ b/modules/meta.py
@@ -279,6 +279,10 @@ class DataFile:
                                     all_init_defaults[dk] = dv
                             elif input_value is None:
                                 optional.append(str(input_key))
+                                if input_key in variables:
+                                    variables.pop(input_key)
+                                if input_key in added_vars:
+                                    added_vars.pop(input_key)
                             elif overwrite_call:
                                 variables[input_key] = input_value
                             else: