Do I need to submit POA to broker for Buyback by submitting offline tender form?

Do I need to submit POA to my broker for applying share Buyback by submitting offline tender form ?
Or Just submitting tender form to broker does it ?
How broker debit my share for buyback without TPIN or POA ?
Is it possible without POA? Or will I get selling authorization with TPIN & OTP when broker process the buyback and debit shares?
Thanks in advance.