Cannot flash Arduino Bootloader on SAMD21G with STLink via SWD programming and openOCD

Question

I'm trying to flash the Arduino Bootloader on a bare ATSAMD21G with STLink via SWD programming and OpenOCD.

These are the steps that I took:

1. Create *.hex file to flash with ArduinoCore-samd repository
2. Connect SWD pins from ST-Link to the ATSAMD21G pins

3. Execute OpenOCD command

   openocd -f interface/stlink-v2.cfg -c "set CHIPNAME at91samd21g18; set ENDIAN little; set CPUTAPID 0x0bc11477; source [find target/at91samdXX.cfg]" -c "init" -c "reset init" -c "load_image {/Path/To/ArduinoCore-samd/bootloaders/zero/samd21_sam_ba.hex} 0 ihex" -c "verify_image {/Path/To/ArduinoCore-samd/bootloaders/zero/samd21_sam_ba.hex} 0 ihex" -c "reset run" -c "exit"
   

4. Command Line output:

   Open On-Chip Debugger 0.10.0
   Licensed under GNU GPL v2
   
   For bug reports, read
       http://openocd.org/doc/doxygen/bugs.html
   Info : auto-selecting first available session transport "hla_swd". To override use 'transport select <transport>'.
   Info : The selected transport took over low-level target control. The results might differ compared to plain JTAG/SWD
   none separate
   adapter speed: 400 kHz
   Info : Unable to match requested speed 400 kHz, using 240 kHz
   Info : Unable to match requested speed 400 kHz, using 240 kHz
   Info : clock speed 240 kHz
   Info : STLINK v2 JTAG v17 API v2 SWIM v0 VID 0x0483 PID 0x3748
   Info : using stlink api v2
   Info : Target voltage: 2.922730
   Info : at91samd21g18.cpu: hardware has 4 breakpoints, 2 watchpoints
   target halted due to debug-request, current mode: Thread
   xPSR: 0x61000000 pc: 0x00000f10 msp: 0x20007ffc
   in procedure 'reset'
   in procedure 'ocd_bouncer'
   in procedure 'ocd_process_reset'
   in procedure 'ocd_process_reset_inner' called at file "embedded:startup.tcl", line 248
   in procedure 'at91samd21g18.cpu' called at file "embedded:startup.tcl", line 331
   in procedure 'ocd_bouncer'
   
   5824 bytes written at address 0x00000000
   downloaded 5824 bytes in 0.132341s (42.976 KiB/s)
   target halted due to breakpoint, current mode: Thread
   xPSR: 0x61000000 pc: 0x2000002e msp: 0x20007ffc
   verified 5824 bytes in 0.481737s (11.806 KiB/s)
   in procedure 'reset'
   in procedure 'ocd_bouncer'
   in procedure 'ocd_process_reset'
   in procedure 'ocd_process_reset_inner' called at file "embedded:startup.tcl", line 248
   in procedure 'at91samd21g18.cpu' called at file "embedded:startup.tcl", line 331
   in procedure 'ocd_bouncer'
   

Really unsure what steps I am missing as it does not seem to flash the bootloader at all. I cannot detect M0 on the USB port after trying to execute the OpenOCD command. Thanks!