faulty randomness (uniform RNG)

dear unity users I am trying to generate uniform random numbers for my tiny game that yields a certain outcome if the generated number is in certain range.

The user bets a certain points and gets a 2x reward if the generated number is above 65, 5x reward if it is above 85 etc

As I sit down and do the math, it should yield 80 reward points for 100 points played. Yet it yields around 65 (I have done this over 100 000 times) I am using Random.value*100 as my random generator where the Random is UnityEngine random not system random.

I also have a big prize condition that requires the number to be higher than 99.99~ even tho I have automnatically played 100k times I didnt see it happening.

I would love to hear possible solutions thanks.