Not validate chalenge dns ttx

My domain is:

I ran this command:
manual from

It produced this output:
Domain “” challenge3 failed. Response from “” was:

Warning: Your verification URL is not returning the correct contents to our verification servers. The URL looks like it is blocking bots and which inadvertently blocks our servers from receiving the correct content. Contact your host, a professional developer or admin for further help with fixing it.

Error: DNS problem: SERVFAIL looking up TXT for - the domain’s nameservers may be malfunctioning

Full Error: { “type”: “dns-01”, “status”: “invalid”, “error”: { “type”: “urn:ietf:params:acme:error:dns”, “detail”: “DNS problem: SERVFAIL looking up TXT for - the domain’s nameservers may be malfunctioning”, “status”: 400 }, “url”: “”, “token”: “-f4PFRFXQZmiTUKJTayDVyWVkJtG1wU8xH_LMPLoHh8” }

vireify from site:
and check from
TXT 1 sec tlFTUesKx6qE0IxBJ6ywj2L7vVDPpL3E_5hgMcVMUAE

What my problem?

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Just like the error message suggests, your nameserver might not working properly. In this case, tests indicate it’s having timeout issue.
There were another test 2 hours ago with same result (NS timeout).
There might be some issue with your name server, e.g. not replying from certain IP unable to connect etc.

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maybe our domain zone banned?

Nope. If it’s forbid issuance, there’s a different message for that.

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I believe this may be the same issue: During secondary validation: DNS problem: query timed out looking up A

@korrel has it resolved for you?


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thnks all,
Our provider blocked letsencrypt ips, so many request for chalenge certs, (like ddos)
Now ips revert to work and certs were are recive

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