nRF52840 flashing issue: Failed to prepare for programming. Could not preserve target memory.

[Usersanme]

Hi
While flashing a hex file, I have the following error ''Failed to prepare for programming. Could not preserve target memory.'' I am using nrf52840 and Segger j-link. you can see the attached photo as a reference. I tried resetting the chip and erasing it beforehand, but nothing changed.
Thanks.

[Simonr]

Hi

Is this a custom board or an nRF52840 DK you're using? If it's a custom board, can you provide some details about said board? What voltage does it run at, how have you connected the nRF52840 to the SEGGER J-Link. I'd also recommend using the nRF Command Line Tools for erasing and flashing your board rather than the J-Link basic commands. 

You can also create a private ticket where you upload your schematics and PCB layouts so we can do a HW review of your design to make sure it is set up correctly.

Best regards,

Simon