Credential test fails on save

Re-check the API Key and Secret. Confirm Domain is the full address with https:// and no trailing slash, e.g. https://acme.ivendnext.com.

"Unable to authenticate"

Keys are wrong or were regenerated. Generate fresh keys in iVendNext and update the credential.

Certificate / SSL error

Only relevant for a temporary test environment. Enable Ignore SSL Issues for that case only; never in production.

Redirect / wrong-address error

The tenant address is slightly off. Verify the exact URL you use to log in and match it exactly.

DocType dropdown is empty

The credential is invalid, or the integration user lacks permission to list Document Types. Re-test the credential; grant the user the needed role.

"Document Type unavailable" / access denied

The integration user has no permission on that Document Type. Add the appropriate role to the user in iVendNext.

A field won't save on Create/Update

Use the field's exact internal name in Meta Fields, and wrap numbers, dates, or line-item tables in an n8n expression.

Line items / child tables not appearing

Pass them as an array via a Meta Field expression (see the Magento orders example, 11.1).

Trigger never fires

Confirm the workflow is Active. Confirm the chosen Event matches the action you take in iVendNext (e.g. On Submit only fires on submit, not on save).

Duplicate triggers firing

An older listener with a similar Trigger Name still exists. Give each trigger a unique name; enable Auto Delete so old ones clean up on deactivation.

iVendNext seems to wait on the workflow

Turn on Respond Immediately in the trigger's Additional Options.

One bad record stops the whole run

Enable Continue On Fail on the node and route errored items to a review/alert branch.

Get Many returns too few rows

Switch Return All on, or raise Limit.

Need to see what happened

Open the workflow's Executions tab — every run is logged step by step with the exact data.