The answer to 'why is my roof vent curling shingles' is that the roof vent is causing the shingles around it to curl and lift up. This is a common issue that can be caused by improper installation, poor ventilation, or damage to the vent itself. Curling shingles around the vent can allow water to leak in, leading to further damage and potential roof leaks.
To fix this problem, you'll need to inspect the roof vent and surrounding shingles. If the vent is not properly installed or has become damaged, you may need to replace it. Ensuring adequate ventilation in the attic space can also help prevent shingle curling. In some cases, you may be able to re-secure the curled shingles, but if the damage is extensive, you may need to replace the affected shingles.