OnePlus India — Oneplus buds Z

I bought the product one year back and send it for repair on 30th april 2022 via OnePlus care app, still under warranty. They picked up from my house and showed it was delivered to service centre after 2 days. After a few days, I got a call from [protected], stating they're from the service centre, they can't do the repair as the production of this item has stopped and they will refund my money. They also asked me to send my bank account details so that they could refund my money. I sent it yo them and they acknowledged the receipt. I waited for few days for my refund and nothing came through. I called back to the above number and they never picked up the call till now. They are intentionally avoiding my calls. I then called to their helpline several times but no help yet. Whenever I call them, they respond as they will soon look into it. Even they told me they'll provide me a voucher code so that I could buy a new product, but that also didn't happen. No response yet. Its a month already. No product or refund I received. I want your help getting my money or product back.