Even though I had booked in advance, the licence plate recognition system made an error reading my plate, the system then blocked me at the barrier with other cars waiting behind and tried to charge me again at an even more extortionate rate! With cars behind growing frustrated I had to buzz staff several times and wait some time before getting any answer, when I finally got through the woman speaking was abrupt in her manner and offered no apologies. I eventually got through the barrier without being charged again however this was an embarrassing situation, no apology offered and my car was trapped unlawfully for a time.