Thank you snap development team for solving this problem
The summary of this topic is
Orbit file problem is resolved by updating snap s1tbx to version 8.0.4, the default you get when you download snap is 8.0.0 so please update.
For GUI users you can check the version by Tools>plugins and check the installed sentinel 1 toolbox kit module.
For non-GUI users check the version by snap --nosplash --nogui --modules --list --refresh
If update is available update by snap --nosplash --nogui --modules --update-all
(here snap is the location of snap in bin)
Another reason snap might not download the orbit file is that you are working behind a proxy, so you need to setup the proxy by going in snap>bin>gpt.vmoptions and setting the following
-Dhttp.proxyHost=http.proxy.ip
-Dhttp.proxyPort=NNNN
-Dhttps.proxyHost=https.proxy.ip
-Dhttps.proxyPort=MMMM
where http(s).proxy.ip is the IP address of your proxy server and NNNN, MMMM their respective ports.
Check your system set up to discover proxy settings, i.e. via:
echo $http_proxy
credits Setting proxy config with command line - #5 by glemoine