Unfortunately I have the exact same issue. The buttons work perfectly for other tasks, but the ifttt integration simply doesn't work. I have tried a few times, and when I opened the ifttt app today I saw that the triggering apparently failed (see attached)
Maybe you can see the same in your ifttt app? If more people have this same issue maybe something could be done.
Latest posts made by rasmusgreve
RE: Flic and IFTTT integration not working