hello all please can help me


******* script runtime error *******
++ must be applied to an int (applied to undefined): (file 'maps/mp/gametypes/_rank.gsc', line 1025)
level.challengeInfo[baseRef]["levels"]++;
*
Error: called from:
(file 'maps/mp/gametypes/_rank.gsc', line 77)
buildChallegeInfo();
*
Error: called from:
(file 'maps/mp/gametypes/_persistence.gsc', line 24)
maps\mp\gametypes\_rank::init();
*
Error: called from:
(file 'maps/mp/gametypes/_globallogic.gsc', line 4224)
thread maps\mp\gametypes\_persistence::init();
*
Error: called from:
(file 'maps/mp/gametypes/_callbacksetup.gsc', line 15)
[[level.callbackStartGameType]]();
*
Error: started from:
(file 'maps/mp/gametypes/_callbacksetup.gsc', line 10)
CodeCallback_StartGameType()
*
Error: ************************************
********************
ERROR: script runtime error
(see console for details)
++ must be applied to an int (applied to undefined)
********************
----- Server Shutdown -----
==== ShutdownGame (1) ====
---------------------------