Overriding properties defined in custom spring-boot-starter doesn't work

Question

On a classpath of my custom spring boot starter some-service-spring-boot-starter there is a application.yaml with bunch of default properties (such as server.port and others). I expected that in consumer app's application.yaml those properties can be overridden, but that's not the case - it looks like starter's config takes precedence over whatever is defined in the application itself. Is this an expected behaviour or am I doing something wrong?