When a reconciliation match is pushed to NetSuite, you may see a synchronization error like this on the match:
Synchronization Error
You have entered an Invalid Field Value 1026 for the following field: account
The message comes from NetSuite, not from Kolleno. The number is the internal ID of a general ledger account, and the field name says which account NetSuite refused:
account, the account the payment is deposited into, taken from your general ledger mapping in Kolleno.aracct, the accounts receivable account it is applied against.
Why NetSuite rejects an account
The customer's subsidiary. Every customer belongs to a primary subsidiary, the payment inherits it, and an account is only valid for the subsidiaries it is shared with. This is why the same bank account reconciles fine for most customers and fails for a few.
The account type. Deposit To expects a bank account and A/R Account an accounts receivable account. Undeposited Funds is the separate Undep. Funds option, not an account you name.
The account itself. It is inactive, or a summary (parent) account that nothing can post to.
Something narrower. A currency, department, location or class restriction, a role restriction that applies to Kolleno's NetSuite user but not to yours, or an internal ID that means nothing in this NetSuite environment.
Check it in NetSuite
Kolleno is subject to the same validation your own users are, so reproduce it by hand. Start an Accept Customer Payment for the customer on the failed match, without saving it, and open the field named in the error.
The account is not offered. NetSuite would refuse it from your team too. Compare the account's Subsidiaries field with the customer's primary subsidiary first.
The account is offered. The cause is narrower, so send the details to Support.
To find which account an internal ID belongs to, go to Lists > Accounting > Accounts and add the Internal ID column.
How to resolve it
Add the missing subsidiary to the account in NetSuite, or tick Include Children on the parent.
Correct the customer's subsidiary if they were set up against the wrong entity.
Map a different account for that bank account.
Nothing is lost while you investigate. The match stays in Kolleno with its error, and you can push it again once the record is corrected. See Manually Retry a Reconciliation Sync.
What to send Support
The Match ID on the failed reconciliation, the full error message, the NetSuite customer and their primary subsidiary, and the name of the account behind the internal ID.