SIHOO M57 Ergonomic Mesh Office Chair, High Back Home Desk Chair with 3D Armrests, Lumbar Support and Adjustable Headrest, Comfortable Computer Chair, Big & Tall Office Chair Hold 330 LBS-Light Grey

Not sure if you are still looking for answers 3 years later, but I googled this topic because I literally have the same problem with my chair at the office, and if I'm not mistaken is the same one that in your picture, or at least super similar. Last week I even took one of the bad kitchen chairs to swap it for the office chair, because the pain was unbearable for me. I'm dreading going to the office, it's like I have a giant bruise in my whole ass whenever I spend the day there. None of my colleagues seem to be experiencing the same issue so I'm kind of glad someone here gets it? At home I have this one (SIHOO M57) and I have never experienced anything like that (and I also sit in every wrong position available 😆 ). I wanted to leave it here in case it helps someone who can actually choose a chair 🥲