If you just added the new supplier, it is sometimes necessary to refresh your supplier/vendor lists to see the new supplier in your dropdown menus.

*From the A/P screen where you enter your paidouts, this refresh dropdown is located on the top bar:

*From the Non-Fuel Invoice screens, you click on the small refresh icon next to the supplier dropdown:



*From the Product Editing > Product Local Attributes screen, use the refresh Vendor button at the top of your screen: