Without knowing anything about your system, your project, your footage etc. nobody can tell you much. Stuff not appearing could mean anything, but really, your post is just completely devoid of any useful info.
We would need some more information. There are multiple ways you could import a Premiere Project into AE.
Please also tell us exact version numbers of both software. We've had some folks on here who said they were on the latest because their CC app said they were up to date, but it was lying to them.
Screenshots of your interface would also possibly be useful. Did you try scrolling up in the composition in AE? Sometimes it'll show past the bottom so it looks like there's nothing there, but you just have to scroll up a bit.
If the workflow is correct and you are using supported media and both AE and PPro are up to date and you have sufficient system resources to be running both programs at the same time it should work. It works for me. I suspect user error or outdated versions or unsupported media.