News Zac Efron Slammed on Social Media For 'MLK Day' Message, Not Appearing at 'HSM' Reunion By Zach Seemayer 11:11 PM PST, January 18, 2016 Now Playing hh:mm:ss Zac Efron is having a rough week on social media.The Dirty Grandpa star is catching flack on Twitter and Instagram for posting what some feel was an insensitive message in celebration of Martin Luther King Jr. Day."I'm grateful for a couple things today: Martin Luther King Jr & 10 million followers on IG," the 28-year-old actor shared on Monday.I'm grateful for a couple things today: Martin Luther King Jr & 10 million followers on IG ☝?✊?#MLKDaypic.twitter.com/R373JoVspQ— Zac Efron (@ZacEfron) January 19, 2016NEWS: Madonna Draws Criticism for Instagram Photos of MLK and MandelaResponses to Efron's tweet were not as supportive of his Instagram milestone.PHOTOS: Star Shots: What's On Instagram?As much hate as Efron got for his MLK Day post, that criticism paled in comparison to the negative feedback he’s receiving for not making it to the upcoming High School Musical 10th anniversary reunion, airing Wednesday.According to Efron, the reunion conflicted with his schedule of promoting his upcoming film, Dirty Grandpa. However, he did prerecord a message for his fans.WATCH: Zac Efron Struggles to Remember the Name of a 'High School Musical' TuneIt seems that this wasn't enough for many HSM fans, who were incensed that he didn't make time for the reunion.@ZacEfron COACH SAID TO FAKE RIGHT AND BREAK LEFT INTO THE REUNION— Karla Alexandra (@karlylemonroe) January 19, 2016All told, it looks like most of his followers have one strong message for Efron: "Get'cha head in the game, Troy!"WATCH: Ashley Tisdale Opens Up About 'High School Musical' Reunion: 'We All Still Love Each Other'EXCLUSIVE: Ashley Tisdale Dishes On 'High School Musical' Reunion and Having Kids Related GalleryStar Shots: What's On Instagram and Snapchat?