Allow Tax Recovery is not enabled in manage Tax Regime, manage Tax

I have completed the Tax setup.

Manager Tax Regime

Manage Tax

Manage Tax Rate and Recovery Rate

but now I am trying setup - Tax Recovery setup.

in Manage Tax Regime - Allow Tax Recovery is unchecked

in Manage Tax - Allow Tax Recovery is unchecked

from edit option - I cannot be able to enable -Allow Tax Recovery - field is grayed out in both manage Tax regime and manage Tax

Please help me - How I can enable Allow Tax Recovery check box in the Manage Tax Regime and Manage Tax

I need to setup one Tax Recovery rate.