Hi everyone.
I'm using a self made pcb with a K32L2B31VLH0A, the way i program the mcu is directly with the mcu USB pins to the pc and the app KinetisFlashTool.exe. I just simply press the nmi_b interrupt button and connect the usb to the computer, the tool recognizes the bootloader and then i'm allowed to program.
This is a picture of the program result, mcu automatically disconnects if i don't mark the box "Auto connect".

When i test the program in my pcb it correctly works, but i realized it no longer connects with the tool once i tried to.
This MCU was a replacement for a MKL27Z64VLH4. When we bought K32s i programed the KL27's hex to the K32 and it worked. I had no problems doing this and i was able to program x times. I don't know if doing this affects something inside the mcu and when i try to program a .hex created for a K32 i'm having troubles. I'm going to program a factory new K32 with its corresponding hex to see if it solves the problem.
To create the project with MCUxpresso i downloaded the sdk for the FRDM K32L2B. Once the code is written the way i'm generated the hex is by doing right click on .axf and then create .hex. The project properties was left by default and the error log isn't showing any errors or warnings.
Does enyone knows what am i possibly doing wrong? What can i do to avoid killing the bootloader?
In case you need the MCUxpresso project to check something just ask for it.
Thank you.