@Faulico , this error is usually and indication that the keystore used for authentication in Constellation has not been sync'd from Infinity. The easiest way to trigger a sync is to clear, save and reset the ConstellationSvcURL DSS. If the Constellation log is available easily, you should see a POST message come in, with the keystore, and other application static assets that are to be cached. If there is no POST into Constellation in the log, check the Infinity log for a http call fail.
@CHRISTIN : Can you help with the steps please.. I have the same issue.. Running the infinity on on-prem and constellation on docker. Is it the SSL key used during the creation of the constellation docker container ?