Checkboxes keep disappearing when adding text in different language

I have the below code:

<div class="wrap"> <div class="add-item"><input type="button" id="addCheckboxItem" class="button button-primary" value="<?php _e( 'Add checkbox', 'sha-wreg' ); ?>"></div> <table id="checkboxes-table"> <thead> <tr valign="top"> <th class="detail-name" colspan="2"><?php _e( 'Checkbox label', 'sha-wreg' ); ?></th> </tr> </thead> <tbody> <?php foreach ( $checkboxes as $field_id => $field_value ): ?> <tr id="detail-<?php echo $field_id; ?>"> <td><input type="text" name="<?php echo $sha_wreg_prefix; ?>checkbox_data[<?php echo $field_id; ?>]" value="<?php echo $field_value; ?>" /></td> <td><button type="button" class="remove-item button" onclick="removeRow('<?php echo $field_id; ?>')">-</button></td> </tr> <?php endforeach; ?> </tbody> </table> </div> <script type="text/javascript"> var prefix = '<?php echo $sha_wreg_prefix; ?>'; </script>

Which outputs as the screenshot below:

The problem I'm getting is I'm trying to translate the text into French and when I go to save the checkbox the entire row disappears like this:

This plugin was custom developed for our Wordpress site by another developer who isn't available anymore. Can someone help me with this issue and let me know why the text keeps disappearing as soon as I add another language?