Rather than pulling directly down, sometimes it's easy to pull on one side, then the other (that saves some of the strain on the plaster board, since the spring presure will be on one side only).
Re fit the fitting ring and that gives you a bit more purchase when pulling, wingle on one side get that down a cm or so and then repeat on the other side. If the thing when in, it will come out!
Re fit the fitting ring and that gives you a bit more purchase when pulling, wingle on one side get that down a cm or so and then repeat on the other side. If the thing when in, it will come out!