Thank you for your feedback. The DreamLine Unidoor shower door that you purchased features a moving door panel that measures 71-3/8" and a stationary panel that measures 72". When the moving panel is installed with the required 5/8" space between the bottom of the shower door and the top of your threshold, the two panels will aline perfectly at the top of your shower door. DreamLine provides the 5/8" spacer to be used on the bottom of the door during the installation process to assure that your panels line up. If your installer removed these and installed the door without them, it is very possible that your shower door was installed at the incorrect height.
We invite you to contact our DreamLine Customer Support Team at 866-731-2244 to discuss this further. Our technician may request photos of your installation to evaluate it. In some cases, we even FaceTime or Skype with customers to view the installation. We can also be reached by sending an email to support@dreamline.com. Our hours of operation are 8am-7pm EST, Monday through Friday and Saturday from 9am-5pm EST. Thank you for choosing DreamLine and for your review. We look forward to helping you soon.