Both sample Java code and Postman for /v1/groups work every time. However when using Spring and RestTemplate i get 401. Even stranger, the code worked occationaly while running it over and over, but I'm not able to reproduce it.
Signature keyId="f97121be-3d1d-493d-8029-5296d1070727",algorithm="hmac-sha256",headers="(request-target) host date",signature="7gxdTU6RcB8FAs1s31U0BNGXtRKgtm+3zjIzYcki8NM="
Mon, 04 Feb 2019 23:37:27 GMT
Authorization: WWW-Authenticate: Signature realm="World-Check One API",algorithm="hmac-sha256",headers="(request-target) host date content-type content-length
Date: Mon, 04 Feb 2019 23:37:43 GMT.
Code used is attached.