Why does certain text message I delete still pop back up

[AC Question]

I have sent text messages to people , and I have deleted the text message. how come in the same day the same message will appear back on my text, but it will appear with a (almost looks like a lock on the message) but I have delete the message several times, is this something on my end, or is this something the person has done.

 

[the tall guy]

Hi, what device do you have? on some phones you can lock certain text message chains, so you might have them locked.