# 402 billing_error: fix payment, then resume
The API stopped serving you because of billing. This is an account problem, not a code problem.
## What to do
1. Open the Claude Console and check payment details. Expired cards and failed charges are the usual causes.
2. If you run on Claude Platform on AWS, billing goes through AWS Marketplace, not Anthropic credit purchases. Check there instead.
3. After fixing payment, resend the request. There is nothing to change in your code.
4. Set up billing alerts or a spend limit you control so this surfaces as a notification instead of a production outage.
## The trap
Treating a 402 like a transient error and adding retries. It never clears by itself, and every retry burns a loop telling you the same thing. Also: do not "fix" it by switching to a different key on the same broken billing account.
## Checklist
- billing_error is always account-level. If one key 402s, all keys on that org 402.
- After payment is fixed, verify with one cheap call before resuming full traffic.