The Period End Date and the Days worked on the pay advice are sourced from the Pay Frequency. If the Pay Frequency Description contains special characters (for example, commas, brackets, dashes) or the number of characters is greater than 40 characters, then the Period End Date and Days Worked won't display.
To display the correct date and days, you need to update the Pay Frequency Description:
Go to Payroll, Maintenance, General, Pay Frequencies.
Edit the Pay Frequency.
Change the Description. Remove special characters and ensure it is no longer than 40 characters (including spaces).
Click Ok to save the record.