Export Undefined index

Hi,

After creating an export my CSV shows the following line on each row:
Notice: Undefined index: wpcf7s_posted-Company in /www/wp-content/plugins/contact-form-submissions/Admin.php on line 534

In each row it states that something is wrong with line 534 although the middle part differs, here are some examples:
Notice: Undefined index: wpcf7s_posted-your-email-factuur in /www/wp-content/plugins/contact-form-submissions/Admin.php on line 534
Notice: Undefined index: wpcf7s_posted-tel-450 in /www/wp-content/plugins/contact-form-submissions/Admin.php on line 534

I’m on the most current version of the plugin, WordPress and theme Divi by Elegant themes. Steps to reproduce:

Export all to csv. I also tried filtering on July to see if the amount of rows has an impact but it also gives the same errors.

Hope someone can help me.

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