Hello Bhavesh Hindocha,
In order to publish from Motion to FCPX, the versions need to be compatible. If you're publishing projects from Motion 5.2, then you need to update FCPX to 10.2 for them to work.
An easy way to think of it for most general situations is:
Motion 5.2 and FCPX 10.2
Motion 5.1.X and FCPX 10.1.X
Motion 5.0.X and FCPX 10.0.X