Lightyear has a ton of built in validation checks to ensure the data is correct in Lightyear before trying to send the bill and information to Sage Business Cloud.
However, there are occasions when the export fails and Lightyear displays the reason for the error - you will see a warning message with information like the below, directing you to view the document's Activity History.
From Sage Cloud: severity:[error] code:[RecordInvalid] source:[line_items.ledger_account] - is invalid
The GL Code in Sage Business Cloud is no longer visible.
Within Sage Business Cloud, go to Settings > Chart of Accounts > search and find the GL being used > select to make visible under Purchase - Invoice/Credit
[From Sage Cloud: severity:[error] code:[RecordInvalid] source:[base] - The transaction date must be later than the year-end lock down date of 01/12/2015. Change the year-end lock down date and try again.</a>]
Within Sage Business Cloud, the Year End Lockdown period has closed.
Go to Settings > Accountancy Dates & VAT > change the Year End Lockdown date. Alternatively, send the invoice back into Approvals/Review and edit the invoice date.