This article covers
[Xero] 1) The document date cannot be before the period lock date, currently set at XX-XX-XX
[Xero] 1) The document date cannot be before the end of year lock date
Summary
This error happens when you have set a lock period for your accounting, and the invoice could not be synced to Xero by the integration for some reason, and the sync is attempted after the account gets locked for those dates.
Solution
To avoid this, you need to address sync problems before your account gets locked.
How to check the lockdate in Xero?
Navigate to Accounting>Advanced>Financial Settings
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