Sleepwell — Causing severe back pain

We bought reflection mattress back in 2019 from Delhi. It started causing back pain issues to both me and my husband but we thought mattress is new may be because of that it’s causing problem. After lockdown we stopped using it for almost more than a year and now started using again. Unfortunately it’s causing us back pain again after we wake up which is so severe. Please take it back and provide full refund