Cotton pillowcases create friction, leading to morning frizz and breakage....

https://shanestue668.yousher.com/why-does-my-hair-get-more-tangled-the-longer-it-gets

Cotton pillowcases create friction, leading to morning frizz and breakage. Switching to silk is a simple fix, but if you’re not ready to swap your bedding, try a loose, soft scrunchie braid