Custom fields Ajax file is not downloading from emails

-- HikaShop version -- : 4.2.3
-- Joomla version -- : 3.9.16
-- PHP version -- : 7.1.33

I have Ajax file custom field in table order. User buys books and after it it gets special certificate which i upload manually to this field. User can access it after logging to his account in order details page and also he gets notification email with this custom field. And there is a link to a file on this email. But this link does nothing. It should download this pdf file i uploaded fro him, but it just doesn't work.

Hi,

Can you place an order on the front like a user, add that same file to the custom field, and send the email to you?
Then, please provide the user access on the frontend and the download link for the PDF so that we can look at the situation ?
If necessary, you can provide that along with a link to this thread via our contact form :
www.hikashop.com/support/contact-us.html

Hi,

From what I understand you have a fatal error during the authorization process which leads to a blank page.
Please turn on the "error reporting" and "debug mode" settings of the Joomla configuration and try to access that download link again.
It should hopefully display an error message which will help us understand what's going on.

set "error reporting" to Development and "debug mode" to on, but still blank screen.

Hi,

Then I don't know. I would need a backend access as well as a FTP access to better understand the situation.
Could you provide that along with a link to this thread via our contact form so that we can look into it ?
www.hikashop.com/support/contact-us.html