I recently went to their ATM to withdraw some cash - 600 euros however, upon checking my bank account statement, it shows that I had withdrawn 800 euros.  When checking with the bank what went wrong, they believe that they had given me 800 euros and not 600!  I do not have the receipts and I do not think their print out proves that the ATM has actually given me 800 euros.  The reason is that I managed to get 600 euros by doing two attempts (first 500 euros and second 100) so I do not understand how this can happen... 

Has this happened to anyone recently?  I am trying to enquire about it but just in case...