Normally ATM will dispense cash if you send the right amount of BTC to the machine in a timely manner. (if you adjust the amount or send it late then no cash will dispense). If the machine sense that your transaction might stay ‘Unconfirmed for a long period of time’ then it will ask for your telephone number. After your transaction has 1-2 transactions it will send sms that says ‘Your cash is waiting! Go to the ATM and press Redeem.’ Then you can go to the machine, enter the telephone number and enter the sms then money will dispense. If you don’t redeem within 24hrs then code will expire. Please note to get refund, I need to wait until your transaction has a few confirmations and 24hrs after the code expires.