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If the mapped pdf has a severe mapping error in which the mapping status for the mapped pdf has a red error icon and there is a mapped field that is in error error such as (Invalid E-form field). You can get this to happen by mapping a field and then go back to the form and delete the field (in the form designer). In this situation, the flow submits but with a warning/error. The pdf the flow will submit and the pdf is generated. If you look at the submission, it The submission is marked in error (yellow triangle). In the above scenario, you will now see the with a icon in the Submissons table. You will see the error: "One or more generated PDF forms generated with mapping errors. Some information may be missing." on the submission.
You can find information about implementing a work-around that will allow international characters in submission PDFs here.
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