according to the debug logs in /var/log/pki/pki-tomcat/ca/, it seems that login permission for certServer.ca.account are not set and the session is not created.
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: CertUserDBAuthentication: UID caadmin authenticated.
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: User ID: caadmin
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: UGSubsystem: retrieving user uid=caadmin,ou=People,dc=ca,dc=pki,dc=nono,dc=org
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: User DN: uid=caadmin,ou=people,dc=ca,dc=pki,dc=nono,dc=org
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: Roles:
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: - Certificate Manager Agents
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: - Administrators
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: - Security Domain Administrators
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: - Enterprise CA Administrators
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: - Enterprise KRA Administrators
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: - Enterprise OCSP Administrators
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: - Enterprise TKS Administrators
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: - Enterprise RA Administrators
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: PKIRealm: - Enterprise TPS Administrators
Here, Granting login permission for certServer.ca.account and Creating session are missing...
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: UGSubsystem: retrieving user uid=caadmin,ou=People,dc=ca,dc=pki,dc=nono,dc=org
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: AAclAuthz: Granting execute permission for certServer.ca.certrequests
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: CertRequestService: Validating certificate request 12
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: DBSSession: reading cn=12,ou=ca,ou=requests,dc=ca,dc=pki,dc=nono,dc=org
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: UGSubsystem: retrieving user uid=caadmin,ou=People,dc=ca,dc=pki,dc=nono,dc=org
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: AAclAuthz: Granting approve permission for certServer.ca.request.profile
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] INFO: CAProcessor: Nonce: 2691022150130176365
2021-02-08 16:22:35 [https-jsse-nio-8443-exec-25] WARNING: CAProcessor: Nonce for cert-request 12 does not exist