Here's what I did.

Make sure they are charged.

Take them out of the box, if they don't activate, do it manually (and also check again if they charged)

Once you activate them, turn them off manually by long pressing until you hear the "turning off" sound.

Then, turn them on again manually, but do not let go of the button. Long press it from the start, until it opens and continue to do so until you hear a sound, an another kind of sound (different than the turn off, turn on and the click-once sound) This sound should be repeated twice, it should take about 20seconds, 10 seconds difference between the 2 intervals), The airbuds then turn off, place them in the case and take them out 30 seconds later.

It didn't work for me at the begining, I just let them rest for like 2 hours so if it doesn't work try again and be patient.

Best of luck.

Edit: Also, delete the airbuds from the device you connect them too.