MobileService.SyncContext.PushAsync never returns in Release build

Question

I am currently trying to create a windows phone app with azure mobile services but somehow offline sync is not working. When I create a release build and call await SyncContext.PushAsync() it never returns back to the context.
I dont really know what is happening,
Code:
 await App.MobileService.SyncContext.PushAsync();
 return true;
When I run a debug build everything works fine.
I can't understand, whats happening in Release mode?
Its a very urgent. Please provide a quick solution or setup a call with me.
Thanks,
Hema
hema

Answer 1

Thank you for the answer, I added HttpMessageHandler to check which operation was causing the problem and a IMobileServiceSyncHandler, as I mentioned earlier when there is nothing to Push the syncing work fine and the pull can be made, but when the push
needs to send data the request passes by OnPushCompleteAsync and does not get to the LoggingHandler.SendAsync or to the ExecuteTableOperationAsync and on the Output console I can see the following exceptions are thrown but the PushAsync does not fail and never
ends.
A first chance exception of type 'System.Resources.MissingManifestResourceException' occurred in mscorlib.ni.dll
A first chance exception of type 'System.Resources.MissingManifestResourceException' occurred in mscorlib.ni.dll
A first chance exception of type 'System.Resources.MissingManifestResourceException' occurred in mscorlib.ni.dll
A first chance exception of type 'System.Resources.MissingManifestResourceException' occurred in mscorlib.ni.dll
A first chance exception of type 'System.Resources.MissingManifestResourceException' occurred in mscorlib.ni.dll
A first chance exception of type 'System.Resources.MissingManifestResourceException' occurred in mscorlib.ni.dll
A first chance exception of type 'System.Resources.MissingManifestResourceException' occurred in mscorlib.ni.dll
The thread 0x1080 has exited with code 259 (0x103).
About the UI, this operation is triggered by the user (button) and is handle in an ICommand in a way that can only be triggered once and locked from other processes with a SemaphoreSlim, I add a little part of the sync code.
await this.MobileServiceClient.SyncContext.PushAsync(cancellationToken);
var query = SyncItemTable.CreateQuery().Where(syncItem => syncItem.UserId == userId);
await SyncItemTable.PullAsync("PullSyncItem", query, true, cancellationToken);
I am using the nugets WindowsAzure.MobileServices, 1.3.1 and WindowsAzure.MobileServices.SQLiteStore, 1.0.1
I appreciate a quick response this is a stopper bug for the next release of our application.