3354569 - Error Logon failed for RESTful Web Services. Contact system administrator

• After upgrade from 4.2 SP7 to 4.3 SP2 P9 and swapping the IP (in load balancer), users are getting an error "Logon failed for RESTful Web Services. Contact system administrator"  while logging into Fiori BI Launchpad (BILP).
• Before swapping IP (in load balancer) it worked [IP swap done on server and hostname maintained]
• Tried KBA 2576124 Error "Logon failed for RESTful Web Services. Contact system administrator." while logging into Fiori BI Launchpad  but issue persists
• Using direct HTTP Tomcat IP Address with Administrator user, BILP is working fine.
• However when using an ldap user and <load balancer URL>/BOE/BI - gives the error "Logon failed for RESTful Web Services. Contact system administrator"
• Implemented kba 2699221 to create separate route/cluster/cookie for biprws - but that didnt fix the problem.

SAP BI 4.3 SP2 P9 upgraded from BI 4.2 SP7 version 
RHEL 7.9
Clustered with 4 nodes
Oracle 19c
Tomcat 9x
Siteminder secure proxy server

BI 4.3 SP02 error biprws siteminder fail restful logon failed authorization  , KBA , BI-BIP-DEP , Webapp Deployment, Networking, Vulnerabilities, Webservices , Problem