Vuforia-Cloud Recognisation not working

I am using Cloud reco for Unity and it doesn't identifying Targets from cloud. steps i done for configuring Vuforia in unity is below :

Unity 5.5.0f3 (64-bit)
- Download Vuforia 6.5
- Add licence key in Vuforia Configuration
- Drag AR Camera from Prefab
- Drag Cloud Recognisition Prefab
- Drag Image Target Prefab
- In cloud recognisition add Secret key and Access key
- in image target select Image Target type : Cloud reco
- but it is not working

Unity 2017.2.0.0f3 (64-bit)
- Download Vuforia 7 from Unity setup
- Add licence key in Vuforia Configuration
- Add AR Camera
- Add Cloud Recognisition
- AR Image Target
- In cloud recognisition add Secret key and Access key
- in image target select Image Target type : Cloud reco
- but it is not working

Unity 2017.3.0.0f3 (64-bit)
- same as 2017.2.0f3

but it doesn't seem to be working in any Unity version it is simply not identifying target i tried running in mobile device too.

 

Have you tested our samples? These can be downloaded from the asset store and include demonstrations of using the Cloud Reco feature.

 

Hey, I tried samples downloading from asset store but unfortunately, it won't work. kindly tell me any other solution. Thank you.

 

Did you enter a license key? Do you see any errors in the log? Did you try in playmode or on device?

 

HI, I checked with my license key, it's perfectly valid and there is no error in the console after scanning. I tried in play mode. actually, I closed this project for some time and now I am back on this project so any help is appreciated. Thank you

Yeah, and now I changed my version to unity to 2017.4.0f1 but sadly it's not working in this version as well.

 

This article solves my problem. sorry for the trouble : https://library.vuforia.com/articles/Solution/How-To-Implement-Cloud-Reco.html