The most recent was them telling me I had to enter a security code that I had previously set up.
It's all because Maestro uses (or replaces) the former national debit card systems throughout the world - and I don't think they thought it through properly. The amount of trouble that UK Maestro users have abroad is one exmple - all because in reality, Maestro is just Switch rebranded, which was never usable outside of the UK (at least as far as I know?).
Why on earth they didn't simply set up Maestro to act as a Mastercard if needs be is entirely beyond me.
Having said this, Lloyds TSB debit cards are a pain in Poland - acceptance of them at cash points seems to be very erratic in nature.