Need a VBS validation code to Block Special Characters in Identifier Field

Summary:

Hello Experts, I need to implement a JavaScript validation that prevents users from entering special characters, alphabets, or spaces in the Identifier field used in the Personal Identifier for External Applications flow.

Content (please ensure you mask any confidential information):

We are using a custom JavaScript rule through Visual Builder Studio, and the requirement is to ensure that the Identifier field accepts only numeric characters. If a user types any alphabet, special character, or space, the system should immediately block it.

This validation must work consistently across the following areas:

• My Client Groups
• Quick Actions
• Personal Identifier for External Applications