I am afraid that you have not given me enough detail on the problem for me even to guess what is wrong with your popup. Is it going down partially, Does the lift crank free-wheel or does the handle not move at all, is there any noise associated with the problem, etc.
I am going to suggest that you visit the Popup Explorer Forums and become a member. The forums are free and there is a lot of great information about all brands of popup trailers there.
Once you become a member you should do a forum post explaining in detail what exactly is happening with your popup Tent Trailer and I am positive that one of the forum members will be able to tell you what to look at to see if you can resolve the problem yourself.
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