Effect of customers using exchanges to deposit

In conducting cash-out transactions, customers should use wallets that they own the keys to.

These are the majority of mobile wallets offered in app stores, and allow the customer to correctly scan the deposit code with the embedded crypto amount, while also sending the transaction immediately upon pressing the send button.

If customers use an exchange or custodial 'wallet' to send to the machine, this often leads to three issues:

• Customers may not be scanning the deposit QR code, and thus entering values by hand, leading to sending incorrect crypto amounts.
• Exchanges typically subtract their withdrawal fee from the sending amount, leading to customers sending less than the required crypto amount.
• Exchanges and custodial services will frequently send batched transactions, which come many minutes later than when the customer actually presses send, thus the machine does not see the transaction on the blockchain before the screen times out.

Each one of these can lead to the transaction not being redeemable and needing to be reconciled because the correct amount is not sent; or the correct amount is sent, but not in a timely manner (and the user chooses not to register their phone number for later cash redemption.)

What happens?

If a customer sends less than the required amount, the machine will not recognise the deposit as complete. Therefore, the transaction should be manually reconciled by the operator (returning the crypto or disbursing the fiat). Before refunding, please ensure to cancel the transaction to prevent any possible later confirmation of the deposit.

If a customer sends the correct amount, but the transaction is broadcasted late (such as the case with a batched send), then after two minutes of not seeing the transaction the deposit screen will time out to the 'Nothing yet...' screen. On this screen the user has the option of either pressing 'No, I haven't [sent coins]', which takes them back to the deposit screen and gives them more time; or 'Yes, I have [sent coins]', which prompts them to confirm their phone number for redeeming the cash after the transaction is seen. If they register their number, and the transaction confirms in the full amount, they'll be able to retrieve their cash.

Avoiding issues 

While we have implemented and continue to work on methods of mitigating incomplete deposits, operators may help reduce such instances by encouraging customers to use true wallets that the customer posseses the keys to, and to avoid sending directly from an exchange.

Further, customers who send to the machine in a batched transaction, though with the correct amount, should be prepared to confirm their phone number with the machine for later redemption. If they decline to do so, the transaction will need to be reconciled manually.

Recommended wallets

There are numerous non-custodial wallets that work as intended with the cryptomat:

• Mycelium
• BitPay
• Copay
• Bitcoin.com
• Eclair
• Coinomi
• Edge
• Samourai
• BRD
• BTC.com
• GreenAddress
• GreenBits
• and more...

However, because exchanges and brokerages are now offering mobile apps, Cryptomat users are still likely to experience issues as these apps deduct their withdrawal fees and send funds significantly later than the user intends.