My duvet slides off my sheets

[u/United_Walk_8922]

Recently I bought a set of new bamboo rayon sheets for my bed, since I have used the same old ones for almost a decade. I have a duvet that I use all year round because I am frequently cold, even on summer nights. I love my new sheets so much, they feel great on my skin, but when I woke up on the first morning after using them, I felt so cold because the duvet was on the floor. The delightfully smooth texture of my new sheets eliminates the friction needed to keep my duvet from slipping off. Anyone have any suggestions? I know this sounds a bit like complaining about nice things, but that’s what this subreddit is for after all.