carry loss back but not full loss can be carried back

[sheendirector]

Hi, my ltd's current year loss is 20K and last year's profit is 25K, I choose to carry back the full amount of loss, however, when I am filing corporate tax for this year, the system only allow me to carry back 18K. I don't understand why there is 2K gap. Anyone know possible reason?

It looks like the system thinks my full loss is only 18K not 20K. No idea why.

Thanks

 

[DWS]

Do you have any items being added back for the tax computations such as entertainment or depreciation which would reduce your loss, they would show on your P&L but are then added back on for tax purposes