Luteina

Could someone help me with a problem? When i use code like that: Clearscreen. Print "START". RCS on. SAS off. LIGHTS off. GEAR off. SET throtlle to 0. WAIT 2. PRINT "NORMALIZED". WAIT 2. SET TargetApoapsis to 80000. Print "Setting Target Apoapsis to 80000". WAIT 2. SET TargetPeriapsis to 80000. PRINT "Setting Target Periapsis to 80000". WAIT 2. PRINT "SETTING MODE TO 1". SET mode to 1. WAIT 2. UNTIL mode = 0 { IF mode = 1 { PRINT "LIFTOFF!". PRINT "MODE I". LOCK Throttle to 1. LOCK steering to heading ( 90 , 90 ). STAGE. Wait until altitude > 9000. SET mode to 2. } else If mode = 2 { PRINT "MODE II". WAIT 1. PRINT "STARTING GRAVITY TURN". WAIT 1. SET TargetPitch to (90 - (1 + (90/41000) * (SHIP:Altitude-8000))). LOCK steering to heading( 90, TargetPitch). Set Z to (TargetApoapsis-1000). If Apoapsis > Z set mode to 3. } else If mode = 3 { LOCK THrottle to 0. PRINT "MODE III". WAIT 1. LOCK HEADING to prograde. PRINT "WAITING FOR APOAPSIS...". WAIT UNTIL ALTITUDE = 70000. SET WARP to 4. WAIT UNTIL ETA:Apoapsis < 30. SET WARP to 1. WAIT UNTIL ETA:Apoapsis < 8. PRINT "APOAPSIS!". SET THROTTLE TO 1. WAIT UNTIL PERIAPSIS > TargetPeriapsis. SET throttle to 0. SET mode to 0. } if STAGE:LIQUIDFUEL < 1 { PRINT "FUEL CHECK". WAIT 1. PRINT "Atempting to Stage". LOCK Throttle to 0. WAIT 1. STAGE. WAIT 1. STAGE. WAIT 1. LOCK THROTTLE to 1. } } I got en error about heading being unrecognized/undefined but when i use part of code like that: SET MODE to 1. IF mode = 1 { PRINT "LIFTOFF!". PRINT "MODE I". LOCK Throttle to 1. LOCK steering to heading ( 90 , 90 ). STAGE. Wait until altitude > 9000. SET mode to 2. } IT works perfectly fine. Please for help.