Plugin is not working

Hello, i have wrote you from the contact us page from your main website, but still didn’t heard from you. Its fine, if you solve my problem here.

I have purchased your wooconvo plugin few months ago, and it was working fine. But now, your plugin is stopped working at all. it is totally a blank page now: http://prntscr.com/rz4sqn and i am not able to send any files from the order page ( http://prntscr.com/rz4ttn ) and customers are not getting any message in their email when i am trying to contact with them from the order conversation page.

Please let me know soon, how to solve these, its very very urgent

Thank you.

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