[BUG] Billing: Subscription plan changed twice without user action; unused-time value consumed by a fully reversed invoice was never restored

Preflight Checklist

• [x] I have searched existing issues and found similar reports (e.g. #56338, #23674) but this is a distinct case with a complete receipt trail
• [x] This is a single bug report
• [x] Note: this concerns Claude.ai subscription billing (Pro/Max plans). Filing here because billing issues have been tracked in this repository and no dedicated public tracker exists for Claude.ai billing.

Summary

Two subscription plan changes occurred on my individual account without any action on my part, and after the second one was reversed, $58.05 of prepaid subscription value was never restored — not as a reinstated plan, not as account credit, and not as a deduction on the subsequent invoice.

Timeline (all documented in receipts, available to Anthropic support on request)

| Date (2026) | Event | Financial effect |
|---|---|---|
| Jan 10 | Purchased Pro annual (valid through Jan 10, 2027) | Paid ~$206 |
| Jun 27 | Plan converted Pro annual → Max 5x monthly — not initiated by me | $107.79 of remaining annual value consumed; $8.57 left as credit; $0 card charge (so it went unnoticed) |
| Jul 11 (early AM KST) | Plan upgraded Max 5x → Max 20x — not initiated by me | Card charged $153.38 + $8.57 credit consumed + $52.77 (+$5.28 VAT) unused Max 5x value consumed |
| Jul 11 | I canceled Max 20x immediately. Invoice fully reversed via credit note ($161.95) | Card refund $153.38 received ✔ / $8.57 credit restored and applied to next invoice ✔ |
| Jul 11 | Re-subscribed to Pro annual | Paid $211.43 ($220 − $8.57 credit) |

Expected behavior

Fully reversing an invoice should restore the account to its pre-transaction position. The $52.77 + VAT ($58.05) of unused Max 5x time (Jul 11–Jul 27) consumed by the reversed invoice should have been either:

• (a) restored by reinstating the Max 5x plan through Jul 27, or
• (b) returned as account credit, or
• (c) applied as a deduction on the subsequent Pro invoice.

Actual behavior

None of the above occurred. The subsequent Pro invoice shows only the $8.57 applied balance. The $58.05 is not visible anywhere in Settings → Billing. The value has simply disappeared.

Additional concern: how were the plan changes triggered?

I never clicked, approved, or requested either plan change. My login email account is secured (password changed, 2FA enabled) and shows no unfamiliar sessions or devices. Since audit/session logs for individual accounts are only accessible internally, only Anthropic can determine whether this was (a) unauthorized account access or (b) an internal billing-system event. Given that it happened twice on one account within 15 days, a systematic cause seems plausible — similar credit-disappearance and plan-change reports exist (e.g. #56338, #23674).

Support-channel note (factual)

The in-app AI support agent gave contradictory responses across the same case (refund confirmed processed → refund denied as ineligible → offered human-agent connection → stated it cannot connect to human agents). A subsequent email reply acknowledged "a genuine gap in the support you should have received" and directed me to request a human review, which I have done. This issue is filed to help the billing/engineering team identify the underlying defect, in parallel with that support case.

Requested resolution

1. Restore the $58.05 in consumed subscription value (account credit or refund).
2. Investigate how two plan changes were triggered without user action, and share findings.
3. If this is a reproducible billing-system defect (plan-change events firing without user consent, and reversal logic not restoring unused-time line items), please fix it — the receipt trail in this case should make the defect traceable.

Environment

• Claude.ai individual subscription (Pro annual / Max 5x / Max 20x involved)
• Region: South Korea (VAT applied)
• Access: web + mobile app

Account identifiers, receipt numbers, and full receipts have been provided to Anthropic support directly and are omitted here for privacy.