Message Oracle PLS-00215 - String length constraints must be in range (1 .. 32767)

ERRORString length constraints must be in range (1 .. 32767)
CAUSEWhen a character variable was declared, a length outside the legal range was specified. For example, the following declarations are illegal: flag CHAR(0); -- illegal; zero length name VARCHAR2(-10); -- illegal; negative length
ACTIONChange the length constraint, making sure that it lies in the range 1 .. 32767.