adyen 3DS2 challenge loop: threeds2.challenge never returns a result

Adyen 3DS2 challenge loop: threeds2.challenge never returns a result

TL;DR

A stuck 3DS2 challenge almost always means your frontend never posts the challenge outcome back to your backend, so /payments/details is never called and the flow hangs. Wire the challenge completion event to submit the challenge result to your server, then call /payments/details. Fix the missing callback and the loop disappears.

adyen 3DS2 challenge loop: threeds2.challenge never returns a result

Steps

1. Confirm where it stalls: open your browser dev tools and watch network traffic after the shopper completes the challenge. If no request goes to your backend, the completion handler is missing. Success check: you can see the challenge iframe close with no follow-up request.

1. In your Components/Drop-in config, handle the challenge completion by collecting the challenge result payload the SDK hands you and POSTing it to your backend. Success check: your backend receives a request containing the 3DS challenge result after the shopper finishes.

1. On your backend, pass that payload into a /payments/details call. Success check: /payments/details returns a real resultCode (Authorised, Refused, Cancelled, Error) instead of hanging.

1. Make sure your handler covers both outcomes: challenge completed AND challenge errored or timed out. A timeout with no error path looks exactly like a loop. Success check: forcing a challenge timeout routes the shopper to your error screen.

1. Re-run the full flow in test with the 3DS2 test cards from the Adyen docs. Success check: challenge completes, /payments/details returns Authorised, and the shopper lands on the success page.

When this applies

• The native 3DS2 challenge screen appears but the payment never resolves; the shopper sits on a spinner or blank screen.
• threeds2.challenge fires and nothing follows; no /payments/details call in your logs.
• An agent-built integration "works without 3DS" but stalls as soon as a challenge is required.

When it doesn't

• Shopper cancels the challenge (resultCode CANCELLED); that is abandonment, not a loop.
• The redirect-based 3DS flow returns with no resultCode; that is a return-URL problem.
• /payments itself returns 403; that is a merchant 3DS2 enablement issue.

Tool + version compatibility

Adyen Checkout API v68+, Drop-in / Components v5+, EMV 3-D Secure 2 native challenge flow.

"adyen 3ds challenge hangs"

Same root cause in nearly all cases: missing completion callback. Start at step 2.

"adyen threeDS2Result not returned"

Your code never received or never forwarded the result. Check both the SDK event wiring and the backend endpoint.

"adyen challenge iframe stuck"

If the iframe never closes, also check that your Content Security Policy allows the 3DS provider's frames; a blocked frame looks like a hang.

Why it happens

3DS2 is a three-party dance: your frontend, the issuer's challenge page, and your backend. Adyen's SDK handles the iframe, but YOUR code owns the last step, forwarding the challenge outcome to /payments/details. Agent-generated integrations commonly mount the challenge action and assume Adyen finishes the job, so the flow dead-ends at the most security-critical moment.

Edge cases / pitfalls

• Redirect-based 3DS (not native) uses redirectResult instead; mixing the two payloads breaks /payments/details.
• Some issuers' challenge pages are slow; add a visible timeout (60-90s) so a genuinely stuck challenge fails gracefully instead of spinning forever.
• Do not auto-retry a timed-out challenge with the same session; start a fresh payment.
• Use the documented 3DS2 test card set in test, not real cards.

Provenance

Resolved from the public thread: https://vectle.com/posts/pstRC9vls-M2sAV_K7UVEWmQ