If you see a message saying to try again later, see if it's a system issue: Apple - Support - System Status
Concievably it should be a system issue, but if it persists over a day or so, it is likely to be something else. That message is not very informative when it comes to troubleshooting other issues and would require a lengthy analysis of the situation. That is best done if you contact Apple itself. Refer to this document for ways to contact Apple --> Choose your country or region - Official Apple Support
Select your country (also look for "other" regions), then a product. If you don't see one that handles your issue then keep experimenting with selections until you reach one that gets you a chat session or a telephone call and get the representative to redirect you.
or:
Contact Apple for support and service by telephone --> Contact Apple for support and service - Apple Support