Blink Example in Keil for NRF52832/ Cortex M4 Error


I am attempting to load a sample blink program onto my BLE Nano 2 on Keil. I am using the particle debugger for my board. When I try to load the program, it gives me an error saying "Error: Flash Download failed - “Cortex-M4"”. Please help. I am very new to all of this.
Thank you,