getting an error on app init() FPWSE0001E: Not Fou

We are getting the following error on application launch.
MobileFirst Platform Foundation version 7.0

error response when calling : WL.Client.connect();

{"status":500,"errorCode":"UNEXPECTED_ERROR","errorMsg":"The server was unable to process the request from the application.         Please try again later."}

error on server side

>com.worklight.core.auth.impl.AuthenticationFilter            E FWLSE0048E: Unhandled exception caught: FPWSE0001E: Not Found - Targeted resource 'PushDevice' does not exist. Check the '17e57139-b8ff-3d29-b105-ddc44
2147adc' parameter
com.ibm.pushworks.server.exceptions.PushWorksEntityNotFoundException: FPWSE0001E: Not Found - Targeted resource 'PushDevice'
does not exist. Check the '17e57139-b8ff-3d29-b105-ddc442147adc' parameter
        at com.ibm.pushworks.server.core.PushServiceImpl.updateDevice(PushServiceImpl.java:461)
        at com.worklight.integration.notification.UserSubscriptionData.addSubscriptionDataToResponse(UserSubscriptionData.jav
a:87)
        at com.worklight.core.auth.impl.LoginContext.addIdentityToJSONResponse(LoginContext.java:438)
        at com.worklight.core.auth.impl.AuthenticationContext.addIdentitiesToResponse(AuthenticationContext.java:522)
        at com.worklight.core.auth.impl.AuthenticationFilter.doFilter(AuthenticationFilter.java:225)
        at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:192)
        at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:86)
        at com.ibm.ws.webcontainer.filter.WebAppFilterManager.doFilter(WebAppFilterManager.java:975)
        at com.ibm.ws.webcontainer.filter.WebAppFilterManager.invokeFilters(WebAppFilterManager.java:1097)
        at com.ibm.ws.webcontainer.servlet.CacheServletWrapper.handleRequest(CacheServletWrapper.java:81)
        at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:912)
        at com.ibm.ws.webcontainer.osgi.DynamicVirtualHost$2.run(DynamicVirtualHost.java:262)
        at com.ibm.ws.http.dispatcher.internal.channel.HttpDispatcherLink$TaskWrapper.run(HttpDispatcherLink.java:938)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1156)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:626)
        at java.lang.Thread.run(Thread.java:780)

But there is no issue while I am testing in my development machine.

The error message that you have provided matches the following APAR:

http://www-01.ibm.com/support/docview.wss?uid=swg1PI41837

As noted on the APAR page, this issue occurs when there are multiple versions of the application installed. The fix for this issue is included in build level IF201507012211 and above. I believe that if you check "About" from your MobileFirst console, you will find that the version that you have is earlier. My suggestion would be to apply the latest ifix to your Studio and Server environments, rebuild/redeploy your project war file, and verify that the issue no longer occurs. Ifixes can be downloaded from the IBM Fix Central site.

Please review the following link for information about installing the ifix and updating the server runtime:

https://www.ibm.com/support/knowledgecenter/SSHS8R_7.0.0/com.ibm.worklight.upgrade.doc/devenv/c_upgrade_to_srvr_in_production_env.html?lang=en