This error message means the tax rate selected on the item or line item may not be compatible with the category selected.
If the tax rate is not available on the tax drop-down menu when looking at the relevant account code in Xero, this means that it cannot be used with the category.
For instance, you are allowed to use tax rates that don’t match the default tax rate, but some types of taxes (eg. income taxes) aren’t applicable to some types of categories (eg. expense).
To resolve this issue, make sure that the tax rate selected in the tax drop-down field on the item (or line item) is compatible with the category selected.
To do this: In Dext Prepare, select a compatible tax rate on the item then try to publish it, even if the error message still persists.