Corexy Not printing in the centre of the build plate

I am struggling to get the Corexy to move to the centre of the bed when printing after homing.
the printer is printing at the orogen point at the front left corner of the bed. any idea how to fix this?

Go back to basics

get a control program such as pronterface
connect it to your printer
move Z somewhere safe
home X and Y
move to X0Y0 (in case you home positions are in -ve) eg G1X0Y0
verify X and Y is at 0,0, if it not you need to adjust MANUAL_{X|Y}_HOME_POS

then tell the machine to move X +100 eg G1X100
measure how far it moved, did it move 100mm?
If not you have a issue with your steps/mm or your micro-stepping is not correct for your steps/mm

then tell the machine to move Y +100 eg G1Y100
measure how far it moved, did it move 100mm?
If not you have a issue with your steps/mm or your micro-stepping is not correct for your steps/mm

Once these are correct check your X_BED_SIZE and Y_BED_SIZE values are correct.
And make sure your slicer has the same bed size or any print wont be centered.

Edited 1 time(s). Last edit at 07/09/2020 09:41AM by Dust.

Thanks dust,
these are steps I have gone through. so am wondering
it there is something I am missing in marlin 2.0x