New Withholding Tax category not appearing in Payables Lines

Summary:

We created new Withholding Tax Rates but they are not visible in the Lines section of Payables invoice creation.

Content (please ensure you mask any confidential information):

Created new Withholding Tax rates via Manage Tax Rates and Tax Recovery Rates, and mirrored setup of existing rates. In the Payables screen, when loading an invoice, the existing withholding rates appear in the "Withholding Tax" section, but the newly created rates do not.

In the cases we are creating, we have two different tax GL strings that should be used for the same rate amount, so trying to create a new percentage to select. (eg NZ_20% where we already have WHT_20% type). The existing rates appear in the relevant selection of payables.