Two things are probably involved depending on where you live--weight of hair pulling out the curl and lower dewpoints because it's that time of the year (heat on in the house also works against the curls.)

A good haircut might help. You can have longer layers to "lighten" things up. The other thing is to add more moisture to counteract the dryer air.
3a (Corkicelli), highlighted, fine, low porosity

HGs: Anything Sevi; Curly Kinks Satin Roots, Curlycue ReNew and Coil Jam; homemade FSG and okra gel; soap bars; UFD Curly Magic; Botanical Spirits Jellies, CJ Repair Me, Aloe Fix