Tds on re-sale property. bought from seller but registration is done by builder. tds 1% on whom?

Hi, I have purchased a re-sale flat from a seller(direct owner) in Dec-2018.Seller has made sale & construction agreement with builder during pre-launch in 2015 but didn't go for registration as he wanted to sell in future. I have paid 62 lakhs to the seller(22 lakhs in cheque, 40 lakh existing loan of seller closed with SBI) and made assignment agreement including both seller/builder

my registration is now complete with the builder and my sale deed is with builder's name. When i have contacted the builder regarding this query he checked with his CA and informed me that i should deposit on his company's PAN number. He informed me that he will pay back me the amount once he receives the return from the government(not sure if he will payback or not) I have below queries 1.My doubt is on whose PAN should i deposit the TDS 1% ? builder or seller? 2.Is it correct to deposit the TDS on builder even though i didn't pay him. BTW on the sale deed his company's PAN number is present.

Thanks, harsha