Been running 2 3220's for years for vpn etc. 4 lines in, mix of BT and virgin. On latest firmware. On Friday afternoon suddenly have internet access problem. Rebooting didn't fix but turning it off and on again did for half an hour or so. So I order another which arrived yesterday. Updated firmware and copied settings across. Worked fine for the rest of the day apart from vpn not connecting. This morning no internet. rebooted and still the same. So put old one back on - at least the vpn will then connect, which it does. However no internet. Emails are fine through office 365. I have changed dns to google. Still not right though. Any ideas?

reinstalled the previous firmware version (3.9.2 to 3.8.9.2) but no change. vpn connects. get emails via office 365 but no internet

You're going to have to find a more structured way to describe and fix this problem...

Starting with "This morning, no internet". What do you actually mean by that? (Given that Office 365 and VPNs use 'the Internet'). Are we talking web browsing?

Surely 4 different lines from two suppliers and 2x3220 can't all have ceased working at the same time?

As things stand, this could be almost anything ... from an unpaid bill on a line, to a dead web proxy.

First categorise which protocol is failing - and what the error messages are. Draytek Vigors have a variety of debug tools built in - but remember that general error messages tend to be reported via SYSLOG. Then it's down to using the standard tools (Ping,Traceroute,Nslookup,Arp etc) ... with ultimate recourse to Wireshark and Port Mirroring (though I bet it doesn't come to that).

(I would advise reversing configuration changes that don't solve the problem ... otherwise you may find you've introduced new problems)