Validates a 10-digit fax number and rejects any input that isn’t exactly 10 digits.

Client-Side Components/Catalog Client Script/Allow 10digit Fax Number/Allow 10digit Fax Number.js

@@ -0,0 +1,12 @@
+function onChange(control, oldValue, newValue, isLoading) {
+   if (isLoading || newValue == '') {
+      return;
+   }
+
+  var faxRegex = /^\d{10}$/; //allow only 10 digit in fax number field
+    if (!faxRegex.test(newValue)) {
+        g_form.addErrorMessage('Please enter a valid 10-digit fax number');
+        g_form.clearValue('fax_num');
+    }
+
+}

Client-Side Components/Catalog Client Script/Allow 10digit Fax Number/README.md

@@ -0,0 +1,2 @@
+This script ensures that the fax number entered consists of exactly 10 digits. 
+Any input that doesn’t meet this requirement — such as numbers with fewer or more digits, letters, or special characters — will be automatically rejected to maintain proper validation and data consistency.