Netsuite Notice on approving vendor bill - You are attempting to create an amortization or revenue recognition schedule outside the range of available accounting periods. Please adjust the periods on this transaction or go to Setup>Accounting>Manage Accounting Periods to set up more periods.

AI generated answer (using internal Slack threads):

The error message you're encountering, "No valid, open, tax period for date - null", is likely due to the fact that the Vendor Bill date falls within a locked tax period. Even though you have subsequent open tax periods, NetSuite will not automatically push the transaction to the next open period. The transaction date must fall within an open tax period. As for the error message "Illegal year format" when creating an accounting period that goes to 2061, it's possible that NetSuite has a limit on how far out you can create accounting periods. Unfortunately, the exact limit is not specified in the NetSuite documentation. Regarding enabling amortization schedules in NetSuite, this feature is part of the Advanced Financials module. If you don't see the option for Amortization Schedule, it's likely that you don't have this module enabled in your NetSuite instance. You may need to purchase this module separately if it's not included in your current NetSuite package. ****** Disclaimer: This response was generated by an artificial intelligence assistant based on previous conversations from multiple Slack channels, and may contain inaccuracies or mistakes. ******