This error could happen if you are importing transactions via AutoInvoice and you have the profile "Sequential Numbering" set to Always Used, but you have not assigned an Automatic document sequence to the document category associated to the tranasction type you are attempting to interface.
Review whether you really want everything (transactions, receipts, adjustments) to use document sequencing. If this was not your intention, it is probably more accurate to set the Profile Option "Sequential Numbering" to Partially Used instead. Either way, you need to make sure that for the transaction types you are interfacing, that you have completed the setup for document sequencing.
Review whether you really want everything (transactions, receipts, adjustments) to use document sequencing. If this was not your intention, it is probably more accurate to set the Profile Option "Sequential Numbering" to Partially Used instead. Either way, you need to make sure that for the transaction types you are interfacing, that you have completed the setup for document sequencing.