I know how you feel as I felt the same when I first started my first set of atma....... but then I tried a different tactic....

Do fates in 1 area for no more than 30 mins (fyi, you dont have to be there for the whole fate or be there at the end of it to get an atma drop), and if I didnt get any drop in that 30 mins I would move on to the next area.

Needless to say I thought my luck had changed as I managed to get my first full set of atma in just over 10hrs of gameplay (I did 4hrs first day and 4hrs 2nd day and 2hrs 3rd day). I didn't count how many fates I participated in, but this tactic worked for me and many other player friends I know who now do the same. It's not a guarantee in anyway, but for some reason you seem to get a better drop chance rate within the first 30 mins of being in a zone. Just rinse and repeat until you're on your last atma.

I can only suggest you give this a try and you never know.