Hello, I'm sorry to see you have this issue. Could you please create a support ticket using the link below:
https://support.sega.com/hc/en-gb/requests/new?ticket_form_id=360003117678
When creating your ticket, can you please tell us what game launcher (Steam, Epic etc.) you are using and if you are playing on PC or Mac.
This error is likely being caused by your firewall or other network configurations preventing the store from connecting.