How do I get Zero Subtotal Checkout back?

Our payment extensions change Magento default behavior to hide the 'zero subtotal checkout' (no payment info necessary) unless there are no other payment methods available.

This allows you to require customers to enter a credit card even if the order is free. This can be important for cases where you expect to have follow up charges, or where you have subscriptions but the initial order is free.

If you don't want that behavior, you can get the 'no payment info needed' option back by setting the minimum order total to 0.01 for all your other payment methods. That will hide the methods for 0.00 totals, and ensure zero total is the only method available and shows up.

You'll find that Minimum Order Total setting in the Magento admin panel in the payment method settings. That's at Admin > Stores > Configuration > Sales > Payment Methods. Please see the extension user manual if you need more detail.