Onboarding: no error shown when Stripe rejects account holder under 18

[stilla]

Summary

When a user under 18 completes the Stripe Connect onboarding flow, Stripe silently rejects the identity verification and pauses payouts. Polar has no error state or user-facing message for this case, leaving the merchant stuck with "Payout account needs setup" and no path forward.

Behavior

• User under 18 completes Stripe Connect onboarding and submits it successfully from their perspective
• Polar dashboard continues to show "Payout account needs setup" / "Onboarding isn't complete yet"
• Stripe dashboard shows an "Actions required" block requesting an identity document, but payouts remain paused regardless because the user is a minor
• The "Submit for review" button on the account review page remains unclickable
• No error message explains what is wrong or that the user does not meet the minimum age requirement

Expected behavior

Polar should detect when a Stripe Connect account cannot enable payouts due to the account holder being under 18 and surface a clear error message during or after onboarding, rather than leaving the user in an indeterminate state.

Suggested fix

• Add an age check (18+) during signup or Stripe Connect onboarding
• If the user is underage, block account creation or surface a clear, specific error explaining the minimum age requirement
• Alternatively, handle the Stripe requirements.disabled_reason or identity verification failure reason and map it to a user-facing message

Example

Org mhnd (ID: ec693aa7-5b0f-437b-bfc1-7d90b32c421a) hit this exact case. Stripe Connect account shows "Enabled" with payments active but payouts paused, with an identity document action required that cannot be resolved because the account holder is under 18.

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