The Sweet Treats Challenge is very flawed.

I am very annoyed with the STS this time.  This weekend I have done 9 challenges so far with a total of 80 rounds.  I always spend sugar/simoleons to get the chance above 92%.  In a normal weekend using that percentage, I loose about 1 per day.  I used to target 90% but that was averaging one lost round per challenge while 92% averages me one lost round per day.  
I have an entertainment budget of $25 per month.  I typically use some of it on The Sims Mobile.  I don't mind spending a little money if the game seems fair and fun.  I really like the game because it seemed fun back when it first launched and I was playing only for free.  Over those first few months, the game worked hard to earn my willingness to spend and commit some of my entertainment dollars to it.  This weekend and this STS has done serious damage to my opinion of the game.
This weekend of the 80 rounds I played, I spent resources to get all percentages above 92%.  I still failed 41 times.  I don't know if they changed the RNG or if they did other tweaking but I am quite cross.  The odds of failing 41 times of 80 when each round has a 92% or higher success rate are astronomically low.  Perhaps they don't value my play or my money.  If this continues, I will simply stop playing.  The hundreds of dollars I've spend on this game over the years of play are a sunk cost.  They only get new money as long as the game is still fun.  Having such a draconic loss percentage is not fun.  If the next STS is the same, it will be my last.