Rihanna apologized for cancelling shows on her "Diamonds" tour due to illness.

Responding to a post on Instagram regarding Monday's missed Houston show, Rihanna explained, "I was sick since San Diego! I kept working because I thought two days off after the Vegas show would be enough time to recover and I f---ed up. Those were two days off from hell and today is not different! I'm sad and disappointed about it! I had all kinds of plans for Houston!"

Unfortunately for Texan fans, Ri-Ri also cancelled her Tuesday Dallas show. Instead, she visited a medical center in Beverly Hills to address her health issues.

However, the "Stay" singer hasn't abandoned her faithful followers. Live Nation asked ticket holders to hang on to them so they can be honored at a later date.

  Angel Diaz