I changed the clock on my 3DS for the real life hour change thing. The next time I played, I've apparently drawn the lotto card for today. I thought 'ok' and forget about it. I played again a few days later, and it happened again. I time travelled to see if it would fix it, but it didn't. What is going on?
I did hear from someone who I cannot remember the name of that when the 3ds and therefor game recognizes a change of time it will disable all in game time based events such as the lottery. So here's the solution to your problem:
If this does not work, wait 48 hours instead and then it definitely should work. If not it's just a glitch and you will no longer have access to time based events. And as a last resort you could try changing your time to the time you had before, or a random time and repeat the above steps.