It looks like the OP may be attempting to send a message that uses one of the new Message features that are not standard text supported on other platforms or devices.
But to paraphrase TSBRICK posting a question without any list of actions taken, context or details is all but pointless since there are too many variables to cover.
So the correct answer to the OP question is: A screen shot.😀
No, that's not from the Messages app. I believe the phone is connected to an Android device (or a non-iPhone device being mistaken for an Android device) through Bluetooth or USB (?)
The Messages app might have been in use at the time, but it's possible that the error/message that came up was in relation to something else and just happened to come up while the Messages app was being used at the time.
The Messages app might have been in use at the time, but it's possible that the error/message that came up was in relation to something else and just happened to come up while the Messages app was being used at the time.