Packages data lost from server

Environment:
Appium version:1.3.5
Platform: IOS
Device: Iphone 6

Description: I am using Appium 1.3.5 (ios) to run the test. The test is a set of Json Payload send/receive between client and server to create an account. The test is going fine until it stuck at one screen that device send JSON Payload to server and wait for response back in order to continue next screen. I see the incomplete data (JSON Payload) response back from server. Therefore my device is stuck at this screen for long time and exit out.

Question: Does anybody encounter the similar issue? Please have suggestions or solutions, I am very appreciated.

Thanks,
Denny