DCB Bank Cashback Debit Card 0.5% on Ecom Transaction

I have used L&T Mutual fund for DCB Bank cashback from last 2 year and earned well. But from 1st Jan 22 LnT Mutual fund stopped investment via Debit Card. Is there any option from Debit card investment  or debit card to bank transfer. 

1. Is there any trading / demat account which provide add money using debit card?

2. Credit Card payment can be done using debit card /  Are there any alternatives  to debit card use?

3. Is there any other alterative can be used for debit card to bank account transfer using bank payment gateway (ecom transaction)?