SAP Message VFRR534 - Time-related revenue recognition needs an accrual start date

Diagnosis
If the item has been indicated as a time-related revenue recognitionitem, it must contain an accrual start date.

System Response
The item is incorrect and cannot be saved.

Procedure
You can only enter the accrual start date in Customizing for the itemcategory. Choose a correct accrual start date in Customizing.