Can't get Swagger UI service endpoints

I am trying to access my Swagger service endpoints. Here is the code:

(defn service-routes []
  ["/api"
   {:middleware [middleware/wrap-formats]
    :swagger {:id ::api}}
   ["" {:no-doc true}
    ["/swagger.json"
     {:get (swagger/create-swagger-handler)}]
    ["/swagger-ui*"
     {:get (swagger-ui/create-swagger-ui-handler
             {:url "api/swagger.json"})}]]
   ["/business-partners"
    {:get
     (fn [_]
       (response/ok (bp/business-partners-list)))}]
   ["/business-partner"
    {:post
     (fn [{:keys [params]}]
       (try
         (bp/save-business-partner params)
         (response/ok {:status :ok})
         (catch Exception e
           (let [{id :business-partners/error-id
                  errors :errors} (ex-data e)]
             (case id
               :validation
               (response/bad-request {:errors errors})
               (response/internal-server-error
                 {:errors {:server-error ["Failed to save message!"]}}))))))}]])

Here is my project.clj:

(defproject businesspartners "0.1.0-SNAPSHOT"

  :description "FIXME: write description"
  :url "http://example.com/FIXME"

  :dependencies [[ch.qos.logback/logback-classic "1.2.3"]
                 [cheshire "5.9.0"]
                 [clojure.java-time "0.3.2"]
                 [cprop "0.1.15"]
                 [expound "0.8.3"]
                 [funcool/struct "1.4.0"]
                 [luminus-http-kit "0.1.6"]
                 [luminus-transit "0.1.2"]
                 [luminus/ring-ttl-session "0.3.3"]
                 [markdown-clj "1.10.1"]
                 [metosin/muuntaja "0.6.6"]
                 [metosin/reitit "0.4.2"]
                 [metosin/ring-http-response "0.9.1"]
                 [mount "0.1.16"]
                 [nrepl "0.6.0"]
                 [org.clojure/clojure "1.10.1"]
                 [org.clojure/tools.cli "0.4.2"]
                 [org.clojure/tools.logging "0.5.0"]
                 [org.clojure/clojurescript "1.10.238" :scope "provided"]
                 [org.webjars.npm/bulma "0.8.0"]
                 [org.webjars.npm/material-icons "0.3.1"]
                 [org.webjars/webjars-locator "0.38"]
                 [ring-webjars "0.2.0"]
                 [ring/ring-core "1.8.0"]
                 [ring/ring-defaults "0.3.2"]
                 [selmer "1.12.18"]
                 [com.novemberain/monger "3.1.0"]
                 [reagent "0.10.0"]
                 [cljs-ajax "0.7.3"]
                 [re-frame "0.12.0"]]

  :min-lein-version "2.0.0"
  
  :source-paths ["src/clj" "src/cljc"]
  :test-paths ["test/clj"]
  :resource-paths ["resources" "target/cljsbuild"]
  :target-path "target/%s/"
  :main ^:skip-aot businesspartners.core

  :plugins [[lein-cljsbuild "1.1.7"]]

  :cljsbuild
  {:builds
   {:app {:source-paths ["src/cljs" "src/cljc"]
          :compiler {:output-to "target/cljsbuild/public/js/app.js"
                     :output-dir "target/cljsbuild/public/js/out"
                     :main "businesspartners.core"
                     :asset-path "/js/out"
                     :optimizations :none
                     :source-map true
                     :pretty-print true}}}}
  :clean-targets
  ^{:protect false}
  [:target-path
   [:cljsbuild :builds :app :compiler :output-dir]
   [:cljsbuild :builds :app :compiler :output-to]]

  :profiles
  {:uberjar {:omit-source true
             :aot :all
             :uberjar-name "businesspartners.jar"
             :source-paths ["env/prod/clj"]
             :resource-paths ["env/prod/resources"]}

   :dev           [:project/dev :profiles/dev]
   :test          [:project/dev :project/test :profiles/test]

   :project/dev  {:jvm-opts ["-Dconf=dev-config.edn"]
                  :dependencies [[pjstadig/humane-test-output "0.10.0"]
                                 [prone "2019-07-08"]
                                 [ring/ring-devel "1.8.0"]
                                 [ring/ring-mock "0.4.0"]]
                  :plugins      [[com.jakemccrary/lein-test-refresh "0.24.1"]
                                 [jonase/eastwood "0.3.5"]]
                  
                  :source-paths ["env/dev/clj"]
                  :resource-paths ["env/dev/resources"]
                  :repl-options {:init-ns user}
                  :injections [(require 'pjstadig.humane-test-output)
                               (pjstadig.humane-test-output/activate!)]}
   :project/test {:jvm-opts ["-Dconf=test-config.edn"]
                  :resource-paths ["env/test/resources"]}
   :profiles/dev {}
   :profiles/test {}})

But when I tried to access http://localhost:3000/api/swagger.json in browser I got this response:

{"swagger":"2.0",
 "x-id":["businesspartners.routes.services/api"],
 "paths":{
   "/api/business-partners": {"get":  {}},
   "/api/business-partner":  {"post": {}}}}

I can't figure out why did I get this in json format and why not see Swagger UI to visaulize and interact with my services? I expect to see something like this: https://ibb.co/TYNT6SG

Start at the service-routes definition and inspect the /swagger.json and /swagger-ui* entry points shown in the issue. Run the application and request both routes, then compare the configured UI URL with the route paths and verify that the expected interactive page loads rather than only the JSON specification.