1- add dependency:

<dependency>
            <groupId>org.springdoc</groupId>
            <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
            <version>2.7.0</version>
</dependency>

2- in spring security(if you are using it), allow following url patterns:

/v3/api-docs/**
/swagger-ui/**

and there you have it! swagger is correctly configured in spring boot