All Checkout.com codes
CHECKOUT.COM · RESPONSE CODE
Checkout.com20003
Invalid merchant or service provider
Checkout.com saysIntegration issue
20003Invalid merchant or service provider
What it means
Merchant account issue
The merchant account is not set up, not active, or not allowed to process this payment.
What to do
Check the account configuration with your provider.
Don't retry as-isWho can fix it: You, the merchant
Yuno response codeINVALID_MERCHANT
Reference only. Codes and descriptions come from each provider's public documentation. The Yuno response code is a reference mapping and does not guarantee how a specific transaction is processed.