Do as Clubman says. It happened to me once at a BOI ATM machine with the receipt saying I had made the withdrawal at 9.0 pm - everything was right on the receipt but the cash was never dispensed . I checked my account online an hour later and the situation had been rectified.
I worked in a bank and delt with ATMs. You have to report the incident to your own branch, it may be the case that the money came out and has automatically been relogged to your account, if not and you have been debted, your branch will than contact the branch that the ATM belongs to. The ATM will then be balanced (this is done every week) it should be over by the amount you tried to withdraw. It can take a few weeks for your account to be rectified
A receipt in these circumstances would not prove that you got the money. The bank really needs to check the 'log' of the machine as that shows any discrepancy between the money left in the machine & what should be there i.e. if there is too little or too much.
Also, IMHO, the environmental effects of not having machines print receipts far outweighs the lack of availability of them. And as I said, the receipts don't prove anything.
Thanks. I have contacted my branch. They will send me a form which on return they check the balance of the ATM in question. Hopefully, I'll get have a credit applied...