Form field data gets lost

The form allows prize entrants to submit from 1 to 3 artwork images. The second page of the form has conditional logic to expose details fields for the second/third items. The fields for the second or third work are not populated in the submission page, or in the field variables used to rename the uploaded images and send emails. The first artwork is fine. The field names are title_1, title_2, title_3 etc. The conditional rules that show these fields as required all works as expected. The error seems to be in parsing the POST data.

This form is based on forms we have previously used for multiple entry prizes. There are no errors in the site logs.

The form is presently set to allow only a single work to be uploaded as we have no way of restoring the lost details entered.

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