If you don't use a gate after you lease it, it will be taken back after a certain amount of time (I believe it's maybe 12 IRL hours but I'm not sure). This is to prevent people from mass leasing gates to prevent competition in worlds where there is a limited amount of gates at the airport as airlines not based in that airport's country can't build a terminal at it.

Hi everyone!

I've been away from playing the game for a year or 2 now due to the pandemic but now that I am back, I would like to offer my help to anyone needing someone experienced to help manage their airline or help improve their profits. I am 10+ year veteran of the game and have placed in the top 10 in ranking in previous rounds. If you are interested feel free to message me and I will consider helping or providing tips. I may be busy in the coming month due to final exams and all the stuff that comes associated with that, but I will try my best to provide feedback and input as well as help manage your airline.