The answer to 'skylight curling' is that the skylight curling is likely caused by improper installation, age, or damage. Symptoms include the skylight frame or glazing material becoming warped or distorted, which can lead to leaks and other issues. Solutions may involve resealing, replacing the skylight, or in some cases, repairing the roof structure around the skylight.
If the curling is minor, it may be possible to DIY the repair. However, for more significant issues, it's best to call a professional roofing contractor who can properly assess the problem and make the necessary repairs to ensure the skylight is functioning correctly and preventing leaks.