I am not getting my gifts / boosters when I reach the treasure chest on Candy Crush .

Hi Amy!

Have you tried playing the game on King.com? I've never had any issues after switching so it might work for you as well.

I saw on another thread a step by step instruction on how to transfer your game progress to King.com:

1) Go to King.com and login then click on settings (cog wheel, top right corner of screen)

2) Choose Account

3) Enter your password

4) Click on Synchronizing/ Connect to Facebook

5) Click on the two arrows to initiate the sync

You can see the tutorial here: https://care.king.com/en/candy-crush-saga/how-can-i-transfer-my-progress-from-facebook-to-the-king-website 

Once done your progress is synchronized and you should now be able to get the treasure chests.

Cheers :-)