[keycloak-user] keycloak.js - token refresh- Bad request 400 - cors

[java_os]

Hi group
Am using ng with keycloak.js (2.5.0.Final).
When token expires keycloak.js is intercepting token expired and does a
renew call when it fails(see client side stack below).
Anyone has any clue around this behavior?
My app is running on 9443 and KC on 8543 over https - all working fine up
to the point when refresh token kicks in.
Behind the scenes is the cors stuff.
Thanks

keycloak.js:451 POST
https://EDIT:8543/auth/realms/EDIT/protocol/openid-connect/token 400 (Bad
Request)

exec @ keycloak.js:451
(anonymous) @ keycloak.js:459

setSuccess @ keycloak.js:773

messageCallback @ keycloak.js:854
:9443/EDIT/#/EDIT/home:1
XMLHttpRequest cannot load
https://EDIT:8543/auth/realms/EDIT/protocol/openid-connect/token. No
'Access-Control-Allow-Origin' header is present on the requested resource.
Origin 'https://EDIT:9443' is therefore not allowed access. The response
had HTTP status code 400.