Phoca cart - file download issues

[icbdigitalmedia]

I am building a photo download site
Process 1. Person views photo->adds it to cart-> add personal details and completes order -> confirms order -> sent a pending email -> order is confirmed for download when payment is received --> sent email with download link.
Photos are in a phocacart-downloads outside the public directory on the web server. the photo is in a folder created by Phoca Cart.

On a test photo, I have managed to get the download link working in the email to customer and it appears on the download page in the browser. However when I click on the link on the download page it presents the error message "File cannot be downloaded"

I have checked with my provider and they say there is nothing on the folder "phocacart-downloads" outside my public directory f that hinders the file being downloaded.

Claude AI suggests that there may be incompatibility between my version of Joomla 5.4.8 and Phoca Cart version 6.1.1
Can anyone advise and make suggestions as to how we can get this file download working,
Its pretty urgent as the event I am photographing is tomorrow!!
Craig Bush NZ