ping errors

Hey all,

I'm seeing errors when checking my ping via ping.nextdns.io:

```

  vultr-lon                 12 ms  (ultralow1)

■ zepto-lon                 error  (ultralow2)

  anexia-lon                error

  fusa-bru                  error

  zepto-bru                 error

  netbarista-par            error

  virtua-par                error

  anexia-par                error

  zepto-ams                 error

  vultr-ams                 error

anycast.dns1.nextdns.io error (anycast1)

anycast.dns2.nextdns.io error (anycast2)

```

test.nextdns.io information:

{
"status": "ok",
"protocol": "DOT",
"profile": "fp52504a14efbe31ac",
"client": "REDACTED",
"srcIP": "REDACTED",
"destIP": "45.90.28.0",
"anycast": true,
"server": "zepto-lon-1",
"clientName": "unknown-dot"
}

Copy

This issue seems to be intermittent, ie; DNS taking FOREVER to resolve, and most of the nextdns servers failing the ping test. But then 2 minutes later, the servers all pass and DNS is quick again. 

What should I be checking to proceed with troubleshooting?