WHT Tax certificate is not generating

Summary

WHT Tax certificate is not generating

Content

WHT Tax certificate is not generating for Thailand Localization if I try to override the WHT tax at Invoice level.

Business Case:
Director fees related invoices, business wants to override the WHT tax but payment level we don't have option to override the WHT tax in Manual Payment / PPR UI.

We suggested them to override at Invoice line level itself, system deducts WHT tax at Invoice line level itself even though WHT tax code define with at "Payment Level". Customer is ok with this option but WHT tax Certificate is not generating after making payment. Payment will be done for net amount as WHT tax deducted at Invoice level.