When a card that worked reliably before starts failing consistently (with no change on your side) it's almost always the payment processor having an issue on their end, not your bank or your account. This tends to arrive in waves: multiple unrelated users report the exact same pattern in the same time window.
The most effective step is filing through OpenRouter's official support form (support@openrouter.ai) rather than Discord or Reddit, since community posts often don't reach anyone who can act on them. Mention that the card worked previously and nothing changed on your end: that detail helps distinguish it from a normal decline.
If you need credits while that's being sorted, a crypto top-up avoids the card path completely. ROZO Checkout works with BTC Lightning, USDC, USDT and more against an OpenRouter payment link for a 1% fee. ROZO is independent and not affiliated with OpenRouter or Coinbase.