Showing "ElementNotFound" error when running almost 60 test cases together

After running almost 60 test cases together, they are not working properly, Showing “ElementNotFound” error for few objects. Same code was working before when I was running them in batch of 10.What can be done for this?

Environment:- OS: MacOS Sierra
version: 10.12.6
Appium Studio version:11.3.82
IDE: Eclipse