UPS pod fails to start with "Unexpected error running Liquibase" message

Issue

• Unable to use Push Notifications feature in RHMAP studio
• Unable to deploy UPS service in the OpenShift console

• UPS pod is not working and following error can be observed

  Liquibase properties - mixing-in environment variables...
  Done.
  Starting Liquibase migration
  Unexpected error running Liquibase: Could not acquire change log lock. Currently locked by ups-1-siy9s (fe80:0:0:0:858:aff:fe01:3dd%eth0) since 7/11/18 12:46 PM
  

• Error Unknown initialization error is shown in Push Notification Tab. Following an example of this message in RHMAP studio.

  Unknown initialization error: {"userDetail":"incorrect keycloak response: 500","systemDetail":"incorrect keycloak response: 500 - Error: incorrect keycloak response: 500\n at /opt/app-root/src/lib/handlers/unifiedpush/gui_routes.js:59:28\n at /opt/app-root/src/lib/util/requestCircuitBreaker.js:61:14\n at /opt/app-root/src/lib/util/circuitBreaker.js:79:12\n at processNextTick (/opt/app-root/src/node_modules/fidelity/lib/index.js:302:28)\n at /opt/app-root/src/node_modules/fh-logger/node_modules/continuation-local-storage/node_modules/async-listener/glue.js:188:31\n at _combinedTickCallback (internal/process/next_tick.js:77:11)\n at process._tickCallback (internal/process/next_tick.js:104:9)","code":"FH-SUPERCORE-ERROR"}