Database error in Language Update

I try to add another language but I get an error message.

like this:

Database error in

Query:

INSERT INTO `sys_localization_languages` (`Name`, `Flag`, `Title`) VALUES ('es', 'es', 'Español')

Mysql error: Duplicate entry '255' for key 1

Found error in the file '/home/*********/public_html/administration/lang_file.php' at line 536.
Called 'query' function with erroneous argument #0.


Debug backtrace:

Array

Mysql error: Duplicate entry '255' for key 1 in sys_localization_languages  thats what it is telling you  there is a 255 already in the db. 

 So how do I solve the problem?

I'm currently have one language on the site And want to add more language to the site. 

In fact it started after adding a NEW_ITEM in the Fields builder in my language and this is the only lang file i have on the site, and now when i try to add another lang file like Spanish i get this error.

remove this " Duplicate entry '255' for key 1" in your database..

Well for some reason it thinks it already has an es  Espanol  file in there.