How to calculate the likelihood of events repeating back to back?

I looked up the odds of missing muddy water three times in a row in pokemon. It’s an 85% accuracy move, so I searched “15% chance event occurring three times in a row” and ai said 0.34% or 1 in 296 events. I stated this in a relevant TikTok and got roasted by a stats bro who said this was utterly wrong. So, IS it wrong? How does one calculate this?