Are you thinking of a duvet, maybe?

I didn't think so either in my case, but my stomach lining didn't agree. I ended up doing a blood test through Everlywell and found out I'm allergic to a hell of a lot of things. I hope your issues clear up soon 💗

Something similar to this happened to me because of food allergies (undiagnosed wheat and milk casein, gastroenteritis for over a week). Can you try switching to plant based ensure?