Airline cancelled my ticket without noticing. Flight was not cancelled. What to do?
 

Hi there,

not long ago, i purchased a flight ticket online (LOT Polish airlines). I had a confirmation number from the airlines.

When i arrive at the airport, they told me that my ticket was cancelled, and that they sent me an email about this cancellation.
I have never received any such email from them, and not a telephone call.

The flight itself was not cancelled, and it left at expected time.

I had to be on this flight, and eventually they wanted 50% of the original ticket value as extra payment for me to go on it.
It felt like a scam.

I'm quite sure it's illegal, and i would appreciate your advice.
what are my rights? what is the best way to deal with this issue?
should i write them a complaint letter? what should i indicate in it? should i report to the authorities?
Surely i want the extra payment i sent back, and also to be compensated for this unpleasant experience.

Thanks a LOT :)