Use RGB to Mix Colors-

I don’t understand what I have missed, thank for help .

Your code so far

<style>
  .red-text {
    color: rgb(255,0,0);
  }
  .orchid-text {
    color: rgb(218,112,214);
  }
  .sienna-text {
    color: rgb(160,82,45);
  }
  .blue-text {
    color: rgb(0,0,255);
  }
</style>

<h1 class="red-text">I am red!</h1>

<h1 class="orchid-text">I am orchid!</h1>

<h1 class="sienna-text">I am sienna!</h1>

<h1 class="blue-text">I am blue!</h1>

Your browser information:

Your Browser User Agent is: Mozilla/5.0 (Linux; Android 5.1; Infinix-X600 Build/LMY47D) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/39.0.0.0 Mobile Safari/537.36.

Link to the challenge:
https://www.freecodecamp.org/challenges/use-rgb-to-mix-colors

All your code worked for me. And challange done successfully.
Try at another browser or in the incognito mode without browser apps and extentions.