Not entirely certain, but it sounds like 'Payment' often associated with a direct payment either by request, Standing Order of Direct Debit. Have you agreed to any contracts in the last month that may relate to this such as mobile phone bill, storecard, utilities etc.
Slips from cashpoints are notorious for being limited in information and even misleading.
I would suggest you call them.
0845 3 000 000
Hope this helps
International Corporate Banker