Swift and Objective C tests When run in parallel fail

I have a project that has some classes developed in Objective-C and Some in Swift and I've written tests also in swift .When I run all tests Swift tests are failing and when I run individual Swift tests by selecting that file the swift tests are passing.

I have the following error when I run all at a time

NSInvalidArgumentException,[NSplaceHolderDictionary initWithObjects:forKeys:Count] attempt to insert nil.

I have Async tests with XCtestExpectation blocks