Creating a Journal Entry where Date is not within the date range of the Accounting Period selected on Posting Period field.
To be able to enter a Journal Entry where date is outside the date range of posting period, the Accounting Preference below and/or Manage Accounting Period Periods page must be considered:
1. Allow Transaction Date Outside of Posting Period is not set to Allow
This can be found at Setup > Accounting > Accounting Preferences > General tab > General Ledger section > Allow Transaction Date Outside of Posting Period drop-down Field.