lets encrypt error on renewal

I am getting since a week, the following error on renewal of a set of domains:
Requesting new certificate order...
new-order error: HTTP/1.1 100 Continue
Expires: Mon, 27 Aug 2018 07:46:57 GMT
Cache-Control: max-age=0, no-cache, no-store
Pragma: no-cache

HTTP/1.1 400 Bad Request
Server: nginx
Content-Type: application/problem+json
Content-Length: 107
Boulder-Requester: 39879028
Replay-Nonce: 30p00hGdTQrCXRIgdHc8kBsO8BhYJ1JGFZ6znS1fJiw
Expires: Mon, 27 Aug 2018 07:46:57 GMT
Cache-Control: max-age=0, no-cache, no-store
Pragma: no-cache
Date: Mon, 27 Aug 2018 07:46:57 GMT
Connection: close

{
"type": "urn:ietfarams:acme:error:malformed",
"detail": "JWS verification error",
"status": 400
}. Exiting...

Used versions:
DA: 1.53.4
CB: 2.0 rev:1908
Lets encrypt: 1.1.10

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