longan-nano-blink: Error when debugging

Hi there,
I have problems with VS code. When debugging the example program longan-nano-blink I got the following error: - - dfuse_download: libusb_control_transfer returned -9
*** [upload] Error 74

I need a solution to fix bugs. I also have the following error when debugging: The command “dfu-suffix” is either misspelled or
could not be found.
*** [.pio \ build \ sipeed-longan-nano \ firmware.bin] Error 1

How can I solve this?

Data:
[env:sipeed-longan-nano]

platform = gd32v

framework = gd32vf103-sdk

board = sipeed-longan-nano

monitor_speed = 115200

upload_protocol = dfu

The second time I have the following error:
Processing sipeed-longan-nano (platform: gd32v; framework: gd32vf103-sdk; board: sipeed-longan-nano)


Verbose mode can be enabled via -v, --verbose option

CONFIGURATION: https://docs.platformio.org/page/boards/gd32v/sipeed-longan-nano.html

PLATFORM: GigaDevice GD32V 1.1.2 #2d0265f > Sipeed Longan Nano

HARDWARE: GD32VF103CBT6 108MHz, 32KB RAM, 128KB Flash

DEBUG: Current (altera-usb-blaster) External (altera-usb-blaster, gd-link, jlink, rv-link, sipeed-rv-debugger, um232h)

PACKAGES: framework-gd32vf103-sdk 1.0.0, toolchain-gd32v 9.2.0

LDF: Library Dependency Finder -> htp://bit.ly/configure-pio-ldf

LDF Modes: Finder ~ chain, Compatibility ~ soft

Found 0 compatible libraries

Scanning dependencies…

No dependencies

Building in debug mode

Checking size .pio\build\sipeed-longan-nano\firmware.elf

Advanced Memory Usage is available via “PlatformIO Home > Project Inspect”

DATA: [= ] 7.0% (used 2310 bytes from 32768 bytes)

PROGRAM: [ ] 4.9% (used 6472 bytes from 131072 bytes)

========================= [SUCCESS] Took 1.24 seconds =========================

Reading symbols from D:\Documents\PlatformIO\Projects\200114-102437-longan-nano-blink.pio\build\sipeed-longan-nano\firmware.elf…

undefinedC:\Users.platformio\packages\toolchain-gd32v\bin\riscv-nuclei-elf-gdb.exe: warning: Couldn’t determine a path for the index cache directory.

PlatformIO Unified Debugger -> htp://bit.ly/pio-debug

PlatformIO: debug_tool = altera-usb-blaster

PlatformIO: Initializing remote target…

GNU MCU Eclipse OpenOCD, 64-bitOpen On-Chip Debugger 0.10.0+dev-00593-g23ad80df4-dirty (2019-06-18-08:21)

Licensed under GNU GPL v2

For bug reports, read

“://openocd.org/doc/doxygen/bugs.html”

Warn : Adapter driver ‘usb_blaster’ did not declare which transports it allows; assuming legacy JTAG-only

Info : only one transport option; autoselect ‘jtag’

Warn : Transport “jtag” was already selected

jtag

adapter speed: 1000 kHz

Info : tcl server disabled

Info : telnet server disabled

Info : usb blaster interface using libftdi

Error: unable to open ftdi device: device not found

How can i fix this?
thx

Did you check that your debug adapter is actually shown in the Windows device manager when you are trying to start the debugging session?