The dome is heavy and held open by springs. The manual: "Do not underestimate the high weight of the lid." Never just let go of it when you close it, keep hands and tools out from between dome and base, and replace damaged springs at once. Dome, hinge and band work needs two people and gloves (the 2016 hinge sheet, written for older grills; the manual's safety page asks the same care).
When the dome overhangs to one side or does not close square, the bands have turned in their ground groove, often after transport (2016 sheet). The fix turns the bands back. This is method B of the 2016 hinge sheet, written for the older Classic.
Glaze dust and tiny chips at the edge of the ground groove are normal (2019 FAQ).
Method B of the 2016 hinge sheet (older grills).