Pepperfry furniture - Misguided with discription for Sofa Purchase

We ordered a sofa online through help pepperfry studio executive at Pune, Wakad, though we wanted to buy it offline by checking our own but most of the items were not available at the studio/store so we were forced to buy it online only.
We thought it would be normal like other sofas we had seen in the studio and the person never described us the difference between online order and sofas kept there in studio, now we have received the sofa on **/**/****, and from day one we felt,it is different than we expected,plus super hard to seat on and constantly giving lower back pain to us which has become a routine now,when we complained pepperfry their person came and checked that the sofa is really hard to seat for long hours on daily basis,but couldn't help us anyways.
Now we requested them that our elders will get serious back pain due to it,if they can get the sofa repaired,or take back or exchange with any offline sofa we are ok to pay the remaining amount but can not use it,as it's super super hard to seat.
They clearly denied for any kind of further help,as our health do not matter to them at all.
Very irresponsible response.