WTax Liable field cannot be found in Form settings window for service type documents

Dear Experts,

I have noticed that WTax Liable field cannot be found in the form settings window for service type documents(Sales and Purchasing).My client is using SAP B1 8.82 version and even in SAP B1 version 9.0 and 9.1 the problem is the same. I haven't found SAP notes on this and even in forums.

Does anyone of you know the cause and the resolution for this?

Thank you.