Upstox — Upstox not closing my account

I submitted Account Closure form in hard copy to Upstox and I got a confirmation of receipt of my form over email on 11.12.2020 but since neither any response is being given by Upstox nor my account is closed.
They have worst Customer care service, we have no option to call or chat. We can just raise ticket which we can't track.
I want to raise complaints to CDSL and SEBI, please suggest way to do it