When I opened my VLC, I was surprised to see a different language, since I am familiar with the interface, I didn't have a hard time changing the language back to my preferred language.
I had searched for the reason that this happened and came here in this forum to see if the reason was stated.
I got surprised by the manner of communication here. I think it is best to be thankful for any kind of help we receive instead of being rude.
Anyway, here are the steps in English for VLC Mac.
1. Click VLC from the menu bar
2. Select Preferences (command+comma buttons)
3. Click the left most button with the cone image that has an orange and green colors. This is located at the upper part of the Preferences window.
4. Click the drop down box / combo box. After clicking you will see the list of
languages.
5. Then select your desired language. Be careful not to select a language that you are not able to read unless you are very familiar with the VLC interface.
5. Restart application.
Peace starts within ourselves! Spread Peace! You are welcome!