OLD MESSAGES APPEARING

***, I have recently come back to apple, I did the IOS transfer, and now every couple of days, my iPhone is adding 400 old texts from 2, 3, 4 years ago. It says they were done Yesterday, but i never sent them nor do i want them. I am sick of it, have been with apple for 4 days, and thinking of getting rid of it already. I don't want 400 OLD messages, i don't even know when they were sent!!. This continues to happen, *** is going on. I have the latest IOS. Turned it off and on, Is iPhone that bad???? How do i just send a message today, and leave it as today. If i scroll down, and open a message, it then goes to the top of the page.