diff --git a/src/modules/flow/form/form.c b/src/modules/flow/form/form.c
index db5ac00b0..8f2ce75b6 100644
--- a/src/modules/flow/form/form.c
+++ b/src/modules/flow/form/form.c
@@ -3226,6 +3226,7 @@ string_formatted_open(struct sol_flow_node *node,
         numeric_field_present = true;
 
         ptr = tmp + 1;
+        sol_buffer_fini(&mdata->formatted_value);
     }
 
     if (!numeric_field_present) {