"JEANNIE! I’m so sorry this happened to you! You don’t deserve it!" Armstrong, 26, captioned a photo of himself and Mai from a past episode. "Your journey on this show was so special so unique and so inspiring! I loved EVERY SINGLE WEEK that we got to go through this together!"
Armstrong also shared his wishes for Mai moving past the competition.
"I hope I helped give you an experience that you’ll remember forever! We share a lot of good times, tough times and all the times in between but mainly, a lot of laughs!" he added. "Mainly you laughing at me but hey I’ll take it! 😂thank you for giving me such an amazing season! We will all be praying for a speedy recovery! ❤️ #teamdreamofjeannie always! 🙏🏽🔥"
Fellow contestant Kaitlyn Bristowe commented on the post, "BUT I DONT WANT YOU GUYS TO GO."
Prior to his Instagram post, Armstrong told Good Morning America of Mai's DWTS departure, "We are devastated by the news that we're going to have to cut this season short, but Jeannie's health does come first. Thank you to all the fans that have helped get us this far and we are praying for a speedy recovery for Jeannie."
Mai announced she was exiting the ABC competition series early Monday in a statement to ET. "My doctors discovered a health concern with my throat which requires immediate attention and surgery. I am heartbroken that my DWTS journey has to end here," read her statement. "The last several weeks have been an amazing learning experience. I have pushed myself to new limits physically and mentally, and I am so proud of how far we’ve come. I can't thank my partner Brandon enough for being so supportive and believing in me."
ABC News reported that Mai was diagnosed with epiglottis, a potentially life threatening inflammatory condition that can cause swelling and block airflow to the lungs, according to the Mayo Clinic.