Web Payments SDK card tokenization timeout on dynamic web application

hdclaims — Thu, 17 Sep 2026 08:52:52 GMT

Hello Square Developer Community,

We are integrating the Square Web Payments SDK to process payment transactions inside a dynamic client intake portal (hdclaims.co.uk).

Issue Description:

When initializing the payments.card() container inside a dynamic DOM view, calling card.tokenize() intermittently throws an UNAUTHORIZED or tokenization_failed error on mobile Safari. The identical API credentials and location ID function properly when tested on desktop Chrome environments.

Technical Setup:

API Version: Square Web Payments SDK v1.x / REST API v2
Target Domain: (hdclaims.co.uk)
Server Stack: Nginx with TLS 1.3 Reverse Proxy
Browsers Affected: Mobile Safari (iOS 17.5), Mobile Chrome 125

Steps Taken:

Validated that Application ID and Location ID match Sandbox/Production environments correctly.
Verified CORS headers (Access-Control-Allow-Origin) explicitly permit origin handshakes from our web application.
Inspected browser console logs; the iframe container generated by Square SDK loses event listener scope when single-page view transitions reload dynamic DOM nodes.

Is there a recommended lifecycle method or re-initialization hook required when re-mounting the Square Web Payments SDK on dynamic .co.uk web applications with client-side DOM updates?

Any technical insights from Square API developers would be greatly appreciated!

thread Web Payments SDK card tokenization timeout on dynamic web application in Payments Troubleshooting

Web Payments SDK card tokenization timeout on dynamic web application