Skechers India — after sales warranty not honoured by skechers

Hello,
I bought a pair of shoes on 15-nov-18 from skechers store at shaheen bagh, okhla, new delhi for rs 2850.
These shoes are advertised and sold by skechers as ultra comfortable in-soles cushions containing memory foam and i bought them for my 70 year old father whose heels pain and so, these guys duped me by convincing me the shoes will retain its in-soles softness for many years and they’ll cover it under their standard warranty.
But, within less than 2 months of very low usage (My father wore them just 4-5 times for a few minutes on every occasion), to much of my shock the in-soles became totally hard and flat, their so called memory foam has flattened totally and now my father cannot wear them at all since he heels hurt badly with theee shoes.
We went back to the store which is 25 kms one way from my home and showed them the problem. They acknowledged the issue but sent us back asking to send an email to skechers customer care (Customercare. [protected]@skechers.com).
We came back and sent the email including the purchase receipt of the shoes and a lot of pictures of shoes showing the problem.
They replied and asked us to go back to the store and deposit the shoes there as the next step.
We again went to the store and they accepted the shoes.
A few days after that, skechers sent me an email simply denying any warranty coverage and saying, they won’t do anything and there’s no issue according to them.
I kept telling them to explain me what did they check but everytime they send me a standard reply saying they cannot do anything.
Hence, here i am before you complaining against skechers and requesting your help.
Thanks