The issue is customer is shipping to Haiti is causing a problem calculating tax
The environment is NAV 2009 R2
The resolution is since they do not want the sales order to be charged tax, they can uncheck Tax Liable checkbox in header.
The cause is Haiti address is defaulted to tax liable.
Note: AvaTax for Microsoft Dynamics NAV 2009 is sunsetted and no longer supported by Avalara as of April 30, 2016. This existing knowledge base documentation is available to provide known paths to resolution for documented issues. If you are using a version affected by service discontinuation and want to maintain access to Avalara Support, you’ll need to upgrade to the latest version of the integration as soon as possible