If you have just closed a month's payroll and you have done so incorrectly, it is possible to reopen the month in question.

Go to Data diagnosis - Tools - Salary utilities - Re-open last month:

If the next month had already been initialized, the first question asked will be :

By saying Yes, the initialization of the new month will be cancelled.

The next question will be (or directly if the new month has not been initialized):

If you answer Yes, the following message will be displayed:

When the operation has been completed, you will be in exactly the same state as you were before you pressed the Closing button.