Fix Subscription Renewal and API Issues

I need help with two issues on a live subscription web app. Stack is Next.js / React, Supabase (auth + Postgres), Stripe billing, deployed on Vercel, using both OpenAI and Anthropic APIs. First, subscription renewals are not resetting the monthly usage quota for paid members - Stripe charges the card but the balance never tops back up, so they're paying and receiving nothing. I suspect the webhook handles new signups but not invoice.payment_succeeded for renewals. Needs diagnosing, fixing, and affected accounts corrected manually. Second, a retired Anthropic model (claude-sonnet-4-20250514) is still being called and failing. I need to know which feature is affected and it migrated to claude-sonnet-5. Note this isn't a one-line swap - temperature, top_p, top_k and assistant prefilling now return 400 errors and must be removed or replaced. Please check the official migration guide. In your proposal, please tell me what you think is causing the first issue and how you'd confirm it. That's what I'll be judging on.