To delete or edit information about a supplier. navigate to the Contacts screen and select the Suppliers table.
To edit suppliers, click on the field you want and edit the value. Changes to the information will save automatically. If a supplier is used on any Purchase orders (PO), the supplier info will also change on those POs.
To delete suppliers, click on the trash can icon at the end of the supplier line of the Suppliers table. If a supplier was used on any Purchase orders (PO), the supplier info will not change on those POs. However, you can't choose a deleted supplier for any new POs.