Need Assistance for Amazon SP-API App Authorization

Amazon SP-API Authorization Consent Page Loading Blank – Seeking Developer Advice.

'm developing an SP-API app ("骏懋gwms", Application ID: amzn1.sp.solution.7d0a8b0d-320b-446f-9723-3e562bd4398d) and running into a frustrating issue with the authorization consent page. When sellers try to authorize via the URL:
https://sellercentral.amazon.com/apps/authorize/consent?application_id=amzn1.application-oa2-client.46403f930f4240d0b960fc6e97d656a2&redirect_uri=https://dev.gwms.jmalltech.com/prod-api/biz/platformAuth/callbacks&state=%257B%2522host%2522%253A%2522http%253A%252F%252Flocalhost%2522%252C%2522redis-key%2522%253A%252219a518e0f8b-26c3deea%2522%257D
The page loads completely blank, with console errors like "Uncaught TypeError: Cannot read properties of undefined (reading 'response')" and other undefined variable issues (e.g., failed to load app details or scripts).
Key details:

The app is published to the Appstore and shows as "Published" in the Developer Console.
Login URI and Redirect URI are correctly set and match exactly (HTTPS, case-sensitive).
When I swap my app's ID with a published third-party one (e.g., Lingxing's appid), the same URL loads the consent page perfectly fine.Tested on multiple browsers (Chrome, Edge), cleared cache/cookies, incognito mode – no luck.
No API calls involved yet; this is purely the consent page failing to render.
Region: Testing on NA marketplace with .com URL.

I've checked roles, Developer Profile, and re-authorized attempts, but the page fails before that. Suspect it might be a backend delay, app ID association error, or URI mismatch, but everything looks correct on my end.
Has anyone encountered this? Any tips on fixing the blank consent page? Or suggestions for what to check next? I'd appreciate any insights or if you've solved something similar.
Thanks in advance!