WooCommerce OTP Checkout Integration

I run a WooCommerce shop on a flatsome theme WordPress site and I want customers to verify their mobile number during checkout and when logging in. The flow is simple:

• On the checkout page the shopper enters a phone number.
• An SMS-based one-time password is dispatched through my chosen third-party API (I’ll supply full docs and keys; it’s neither Twilio nor Nexmo).
• The shopper types the OTP in the field that appears.
• Only a valid code unlocks the “Place order” button.

If the number is new, your code should quietly create a WordPress/WooCommerce customer account tied to that phone, skipping the usual email + password routine. When the number already exists, the same OTP step simply logs the user in and carries on with checkout. No verification is required anywhere else—just checkout and the resulting login session.

I’d like this packaged as a lightweight plugin or a self-contained snippet that won’t break theme updates. Please include clear setup instructions and a way for me to change SMS gateway credentials later. Basic acceptance criteria: OTP must arrive in under 60 seconds, invalid codes must block checkout, and successful orders must be recorded as normal in WooCommerce.

If you have previous experience with SMS OTP flows in WooCommerce, let’s get this live soon.