Springboot application startup error - cannot resolve identifier in the sample bpmn file

We are trying to integrate the flowable-spring-boot-starter-rest project into an existing springboot application (updated to latest with data-jpa and mysql dependencies) and have issues starting up because of unknown expression in the sample bpmn file.

I was able to test out the spring boot integration in a standalone skeleton project by following the instructions here https://www.flowable.org/docs/userguide/index.html#springSpringBoot The sample works fine and no issues with the expression in the userTask.

When i try to integrate this same sample bpmn file with the existing codebase, it works fine when the bpmn file contains kermit as the assignee, but when i try to switch to an expression as below

userTask id=“theTask” name=“my task” flowable:assignee="${user.userID}" in the xml

the app fails to boot up with the following error -

Caused by: org.flowable.common.engine.api.FlowableException: Unknown property used in expression: ${user.userID}
at org.flowable.common.engine.impl.el.JuelExpression.getValue(JuelExpression.java:50) ~[flowable-engine-common-6.4.2.jar:6.4.2]
at org.flowable.engine.impl.bpmn.behavior.UserTaskActivityBehavior.handleAssignments(UserTaskActivityBehavior.java:272) ~[flowable-engine-6.4.2.jar:6.4.2]
at …
… 10 common frames omitted
Caused by: org.flowable.common.engine.impl.javax.el.PropertyNotFoundException: Cannot resolve identifier ‘user’
at org.flowable.common.engine.impl.de.odysseus.el.tree.impl.ast.AstIdentifier.eval(AstIdentifier.java:97) ~[flowable-engine-common-6.4.2.jar:6.4.2]
at org.flowable.common.engine.impl.de.odysseus.el.tree.impl.ast.AstProperty.eval(AstProperty.java:68) ~[flowable-engine-common-6.4.2.jar:6.4.2]
at org.flowable.common.engine.impl.de.odysseus.el.tree.impl.ast.AstEval.eval(AstEval.java:53) ~[flowable-engine-common-6.4.2.jar:6.4.2]
… 32 common frames omitted

The user object is an existing entity and not sure if am missing something here. I was wondering if someone could point me in the right direction to debug through this issue.