AI Model started to miss a delimiter in the invoice.

Hi,

So we've been trying to use AI Builder to read standardized, invoices in PDF documents (not scans, no images, plain text).

We have used both the invoice ready template and fixed template documents to train the model.
We have used around 20 documents, with various scenarios, one-page of products, two pages.

The pre-defined invoice model have correctly found the items lines in the invoice, and correctly read the values with delimiters in tables.

It worked as magic for some time, but recently, the model started to miss the decimal delimiter (comma ",") but only in the >1 items invoiced. We had 2 collection for training. Single items and multi-items with >1. I think it could have something to do with published model used from 3.1 to 4.0, but can't confirm.

Now it can read all the total values and so on correctly for all documents, but for multi-lines it can't read only the items-lines. Digits are read perfectly, but commas are missed. i.e it reads 58,58 as 5858. The delimiter in number field amount is set to comma, have tried changing to text but it's the same.

Anyone had such issues, or any experience how can I maybe adjust collections to re-train the model, because i suppose this is the only way to fix it right now? Or how can I revert the model version to 3.1 to confirm it was after the update?