SharePoint 2013 Language Resource Issue

We have created website in SharePoint 2013, It have English, Arabic and Fresh version already which are working very good.

Now we have new requirement to create Italian language, So I created new Variation Label Italy and Created hierarchy. Job run successfully and created variation pages.

Now issue is we have wsp where there is translation for each language. Until now we have resource file for English, Arabic and French they are working properly. Now I added new resource file for Italian language and deployed to the SharePoint, but SharePoint is not detecting Italian resource file and it always pick English resource file.

Kindly somebody can tell me what I am doing mistake.