Originally Posted by Zenithale

That's in fact 1, 3 and 7. So if we need to restart each time it should be 1+3+7 = 11 DF, but we need probably only 7.

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(To be more clear, the first DF reward is a 4* Ticket, for 3 DF we get a 5* Ticket, and then, at 7 DF we get another 5* Ticket.)

The banner below the game is a bit clearer (No idea if direct linking the image here works properly, otherwise just look on the Flower Girl page, it's all the way to the bottom of the banner:



So,
First Dreamfest: 1x 4* ticket
Three more Dreamfests: 1x 5* ticket
Another three Dreamfests: 1x 5* ticket + 5x Silver Awards