// Fixed by lowering the swagger version to 2.7.0

@EnableWebSecurity
@Configuration
public class ResourceServerConfig extends WebSecurityConfigurerAdapter {
//...//
    public static final String[] AUTH_WHITELIST = {
        "/swagger-ui.html/**", "/configuration/**", "/swagger-resources/**", "/v2/api-docs", "/webjars/**"
    };
//...//

    @Override
    public void configure(WebSecurity web) throws Exception {
        web.ignoring().mvcMatchers(HttpMethod.OPTIONS, "/**");
        web.ignoring().antMatchers(AUTH_WHITELIST);
    }
  
}