24 hour clock timestamp in iMessage OS

I came upon the question searching for the answer and 10 people said they had the question of "Why doesn't iMessage show 24HR time even though I have selected 24HR time for my clock?".

The answer is to go to date and time in preferences and select the tab on the bottom which says, "Open Language and Region". Once the tab is open the user will see the selection available as the current time with AM/PM, select this box to expand the choices and click on the 24HR tab and now the entire computer will be 24 HR time.

Cheers