You're the victim of a very common mis-perception in probability, the so called 'memoryless' random independent event.

In other words, every time the rng kicks in there is a set probability (lets say 22%), and if it comes up false (so, it was a 'failure'), and you try again, there is still ONLY a 22% chance of success.

Now, it may seem unfair that you got 20 melds that didn't workout in a row, but really, you could get an infinite number of failures in a row, because the probability is memory less, and doesn't care what came before it when it's a random independent event such as this. (Ok, not really infinite since you could make the probability for successive failures would approach 0, you'd get it eventually assuming a continuous infinite time scale, but you get the idea).

That all being said, there is a certain probability that can be applied to determine the odds of rolling 20 fails in a row given a probability of 22% for each event, and it would be relatively low.