Welcome to the Candy Crush Saga Community
Do you have a question or need help with your game? Ask the Community.
Most likely you are playing on Facebook as lately there have been a lot of complaints from people losing their gold when they play through Facebook.
Alternatively you have deleted and reinstalled the app as this will also delete your gold.
Possibly you have not been saving your game and an update of your device has wiped the game from its memory.
If you are earning gold every day and losing it then that is a different matter as all gold is stored on King's servers, so unless you delete it (as indicated above) it should be safe.
Do you sign into your game with a password and email?