diff --git a/dataio.c b/dataio.c
index 4dd42f8..ff28cf4 100644
--- a/dataio.c
+++ b/dataio.c
@@ -18,20 +18,23 @@ int modify_credit(name, price)
     person_data = fopen(filename, "r");
 
     if (person_data == NULL) {
-        printf("Warning: Filename %s does not exist! Creating...\n", filename);
+        printf("Warning: Filename %s does not exist!\n", filename);
         credit = 0;
     } else {
         fscanf(person_data, "%i", &credit);
         fclose(person_data);
     }
 
-    credit += price;
-    person_data = fopen(filename, "w");
-    if (person_data == NULL) {
-        printf("ERROR: Filename %s could not be created or overwritten!\nCheck system integrity!\n", filename);
-    } else {
-        fprintf(person_data, "%i", credit);
-        fclose(person_data);
+    // Write only if the price would change credit
+    if (price != 0) {
+        credit += price;
+        person_data = fopen(filename, "w");
+        if (person_data == NULL) {
+            printf("ERROR: Filename %s could not be created or overwritten!\nCheck system integrity!\n", filename);
+        } else {
+            fprintf(person_data, "%i", credit);
+            fclose(person_data);
+        }
     }
 
     return credit;