Printer start print at the top of z axis

Today I install MKS gen L board in to my CR10 and I flash it with Marlin 1.1.9
Now I have the problem. When I start to print the printer heat the bed and nozzle then it preform the home action and that is ok. But when it shud start print move z-axis all the top and start print in the air.
Can some one please help me.
I can’t attach the configuration file because I’m new user

hi it have set you to new user and welcome.