Zip Attachments Plugin not working

I noticed that other people reported issues with the plugin. We recently had a similar issue where zip files didn’t work. We ended up opening the zip files in our code editor, and found the following error:

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<b>Notice</b>:  Constant zip_attachments_path already defined in <b>/var/www/html/wp-content/plugins/zip-attachments/download.php</b> on line <b>12</b><br />

With that error in mind, we removed the same definition in the file ‘zip-attachments.php’ on line 18. This fixed the error. So there should probably be a conditional statement for this definition, in order to avoid errors in the future.