If your text messages on iPhone turn green instead of blue, it might indicate that someone has blocked you. Green messages typically mean that your text is being sent as a regular SMS instead of an iMessage. However, it is crucial to note that it's not a foolproof sign of being blocked. The best way to confirm if you've been blocked is to check for delivered notifications under the messages you've sent to that person. If you see that the "delivered" status is missing, it could potentially mean that the person has blocked you. Keep in mind that there could be other reasons for green messages, such as network issues or the recipient's settings.