Take some time to adjust your ergonomic chair so it matches your body. You can adapt fast and with comfort, yet seat height, backrest angle, and armrest position do affect this. Their influence determines comfort and adaptation speed.
Your body might continue compensating for poor angles if you jump upon your new chair without properly setting it up. Your muscles will settle with more quickness once that height allows your feet to rest flat as your back is supported plus your elbows fall in line with your desk.
Become familiar with each of the chair’s features during this early period. Adjust the chair better for your body to increase speed. Then the chair becomes as an extension of your routine and not just another seat.
Once you fully adjust for comfort, focus, and posture, a noticeable improvement will occur, but yes, you may need a few days.