Hi @Ankit – a Verified Customer is able to transact from wallet to wallet if they have funds in the Balance loaded from some bank funding-source. In Sandbox, you likely pre-loaded the Verified Customer’s wallet (Balance) from the test funds in your Master Account’s Balance or Superhero Savings Bank account, but in Production, the funds will need to arrive into the Dwolla network somehow.
All Customers will need to have a bank account attached if they want to create transfers to/from the bank account. Otherwise, it’s not a requirement that they have a funding-source attached in order to just create wallet-to-wallet transfers.
Hope that helps! Let me know if you have any questions or need any recommendations for your specific use case!