Upgrade from Plus to Pro fails before payment form loads — no Stripe/card entry UI, /backend-api/subscriptions/update returns 400

Hi @sei6 Welcome to the dev community. This definitely doesn’t look like a normal card failure. The payment step never even loads, which usually means the upgrade flow is failing earlier on the backend side. Really appreciate you listing everything you’ve already tested, that helps rule out most of the usual causes. One workaround that sometimes helps in this specific Plus - Pro transition is resetting the subscription state: * Cancel the current Plus plan * Wait for it to fully expire * Then try subscribing directly to Pro instead of upgrading Not ideal, but it can bypass cases where the upgrade path gets stuck. If you’re still seeing the same behavior after that, it’s worth opening a support ticket so the team can take a closer look at the account and billing state. When you do, include what you already shared here (especially the /subscriptions/update 400 detail), since that’s actually very useful signal. ~Smith