It is straightforward to solve the issue of SMP not calculating.
This happens because your worker does not have 26 weeks of timesheets in PAB. You will need to use the override in the SMP History Screen.
📌 Note: This should only be used if the overridden value is not being applied with the Force SMP Payable set as AUTO.
To force SMP through on a worker:
Click Payroll, then select Statutory Payments Maintenance.
Select SMP History Maintenance and press Ctrl+M to enter Modify Mode.
Select the Use Override check box.
Type the Overridden Value.
Change the Force SMP Payable drop-down to YES.
Run the Statutory calculation as normal.