The airline is responsible for the carriage of passengers and luggage.
The rights of air passengers include the following areas:
If you believe that your rights arising from the regulation on air passengers have been breached, you should first contact the airline. In case of problems related to persons with reduced mobility, you should contact the airport. If you are not satisfied with their reply, you can file a complaint with a National Enforcement Body (NEB). In principle, complaints should be filled in the country where the incident took place.
Responsible authority in the Czech Republic:
CIVIL AVIATION AUTHORITY
Letiště Ruzyně, 160 08 PRAHA 6
Tel.: 225 422 267
Fax: 225 421 990
E-mail: firstname.lastname@example.org nebo email@example.com
You can find more information here.