Cannot retrieve form from server

Hello Everyone and thank you.
I have tried several deployments in our servers (Debian, CentOS and Ubuntu Server) and i cannot retrieve the forms to get a preview.
My last try was on the Ubuntu Server machine using the kobo-install script and i got the error “Form could not be retrieved from server”. When i check the logs i get the following message:
“POST /transform/xform HTTP/1.0” 500 (88 bytes) “https://ee.mydomain.tld/preview?form=http://kc.mydomain.tld/asset_snapshots/sgkVhy6HUYYUSqYe6poNmZ.xml” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.131 Safari/537.36”.
I have tried with several browsers and deployment types (http/https) and the issue is the same.
Thank you for your support