If your hair gets frizzy or flat on day 2 from laying on it at night that can help. I haven’t tried it but I’ve heard good things about this one.
Funcl Womens Sleep Night Cap Wide Band Polyester Bonnet for Hair Beauty,Hair Care Cap,Chemo Beanie,Curly Springy Hair https://www.amazon.com/dp/B07FRKTMVT/ref=cm_sw_r_cp_api_glt_fabc_VPAWSZVDJAGCRGH0C67F?_encoding=UTF8&psc=1
I got this one from amazon: Funcl Womens Sleep Night Cap Wide... https://www.amazon.com/dp/B07FRKTMVT?ref=ppx_pop_mob_ap_share
It’s a little roomier for a LOT of hair and the wide headband stays on my head all night. Fair warning, it has been staining my pillow case even though I washed it when I got it. It’s not a HUGE deal because I have all white bedding and I just bleach them to hell every time I wash. But I’m sure washing the bonnet by hand a few more times will get the excess dye out.
I bought this one, which was recommended by Manes by Mel (worn by her sister). I have found that the thick band helps it stay put during the night as long as i have the band on my forehead. It is super comfortable.
https://www.amazon.com/gp/product/B07FRKTMVT/ref=ppx_yo_dt_b_asin_image_o01_s00?ie=UTF8&th=1
Another recommendation is to do bobby pins on the side, by your ear, to hold it in place.