I have a Galaxy S4 Active and all my messages are on one side, how do I change it back?

[AC Question]

i have a galaxys s4 active all my messages are on one side how to i change it back

my phones text messages are not one after the other like normal my messages are all in a line down the right side and the person im texting messages are on the left down a line I have to sscroll up just to read them