System version: miui 1 1.3
Software version: Pinduoduo 5.4 1.0.
1. Click on the personal center interface to enter Duoduo wallet.
2. After entering the wallet, click more buttons in the upper right corner.
3. Click Enter Bank Card in the pop-up menu below.
4. Click to enter the bound bank card.
5. Click More in the upper right corner of the bank card interface.
6. Click the Unbind pop-up below.
7. Finally, confirm the unbinding.