Flipkart — Return pickup issue| No help from flipkart

Website: www.flipkart.com

I ordered a WFH chair from Flipkart and got it delivered on 19 Aug Thursday but one of the wheel holder was damaged and I requested for a return, The technician came the very next day i.e: 20th Aug Friday, and accepted my return request and said a person will come for pick up next day, So on Saturday 21st Aug the person came and said he won't be able to take the product until it would be dismantled...I don't know how to do it nor is there a manual on how to dismantle it.

I've been trying to contact Flipkart since Sunday i.e: 21st Aug all they say is I have to dismantle it or take outside help and said they won't be sending their technician or any help from their side.