It might gettting corrupted or error if the theme is bigger than the upload limit size which you can’t upload a files bigger than 10MB.
I highly suggest you to manually install or upload your astra theme(plate) by FTP manager and then just activate it on dashboard after uploading. Your theme(plate) must be splitted, so you know.
The template server might be down or the IP address of free hosting servers might be blocked by their firewall.
Had you contacted the support team of your theme regarding this problem?
This sounds like the template server is down, not a hosting issue.
Sure, it could be a firewalling issue on the client server. But I don’t see any reason why our servers would have such a thing, so the template server having an issue is more likely.
Of course, it might be a sever error. But please double check with the theme developer that the template server isn’t down.
And if it isn’t, could you also ask them where and how this “template server” can be reached so I can actually investigate this?