Hi, we are sorry to hear about your experience. Could you please fill out the form on this page so that we can check it for you?
https://help.flixbus.com/s/article/PSSP-I-would-like-to-give-feedback-about-FlixBus-equipment-How-can-I-do-this?language=en_IE
Thank you very much for your understanding.
Best, Your FlixBus Team