I can't connect with WPMU Dev Dashboard & I can't download any plugin

I can not connect to my WPMU DEV Dashboard.
When I try to connect that error show me:

Your server had a problem connecting to WPMU DEV: "Error unserializing remote response.". Please try again.

If this problem continues, please contact your host with this error message and ask:

"Is php on my server properly configured to be able to contact https://premium.wpmudev.org/api/dashboard/v1/ with a POST HTTP request via fsockopen or CURL?"

Also when I try to download any plugin from your website, the download crashes.