Not allowed to start service Intent

[UzairDawood]

      Fatal Exception: java.lang.IllegalStateException: Not allowed to start service Intent { cmp=com.mpm.launcher/com.somsakelect.android.mqtt.MqttService }: app is in background uid UidRecord{483ea5c u0a130 CEM  bg:+2m11s553ms idle change:cached procs:1 seq(0,0,0)}
   at android.app.ContextImpl.startServiceCommon(ContextImpl.java:1715)
   at android.app.ContextImpl.startService(ContextImpl.java:1670)
   at android.content.ContextWrapper.startService(ContextWrapper.java:720)
   at com.somsakelect.android.mqtt.MqttAndroidClient.connect(MqttAndroidClient.java:411)
   at com.mpm.launcher.MQTT.MqttClientHelper.lambda$create$0$MqttClientHelper(MqttClientHelper.java:96)
   at com.mpm.launcher.MQTT.-$$Lambda$MqttClientHelper$PqXP57ty9z8XdEyemLhbfuHLmIY.run(:4)
   at android.os.Handler.handleCallback(Handler.java:938)
   at android.os.Handler.dispatchMessage(Handler.java:99)
   at android.os.Looper.loop(Looper.java:223)
   at android.app.ActivityThread.main(ActivityThread.java:7664)
   at java.lang.reflect.Method.invoke(Method.java)
   at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
    

getting this crash sometime on android 11 but all time i don't understand what to do