Sandbox MID returning 703 "Internal Error" on Pay by Bank / TeleCheck operations

[myartsev]

Product

CommerceHub

Page

APIs

Description

Hi,

I'm integrating with Commerce Hub Pay by Bank (ACH) via the certification sandbox environment and consistently receiving a 703 Internal Error from the gateway processor on all TeleCheck-related operations.

Details:

• Workspace: PaymentLocal
• MID: 100008000003683
• Terminal ID: 10000001
• API Key Name: comhub-cert-ccci-sandbox
• Environment: cert (connect-cert.fiservapis.com/ch/)
• Entitlements: Check Acceptance is enabled on the merchant
• Features: Payments + Payments: Value Added Services

What I've tried:

• POST /payments/v1/charges with sourceType: "PaymentCheck" → 703
• POST /payments-vas/v1/tokens with Pay-By-Bank-Create → 703
• Card-based charges via PaymentCard reach the gateway successfully (704 timeout, not 703)
• /status health check returns healthy (no 5xx errors)

Sample error response:

  {
    "gatewayResponse": {
      "transactionType": "TOKENIZE",
      "transactionState": "DECLINED"
    },
    "error": [{ "type": "GATEWAY", "code": "703", "message": "Internal Error" }]
  }

Could you verify that TeleCheck / Pay by Bank processing is properly configured and active for this sandbox MID? Or if there's something wrong with the gateway itself? Thanks!

Expected Behaviour

The API calls return a 200 response

Operating system

Sequoia 15.6.1

Browser

N/A

Region

No response