Hailo15 with USB camera

I want to use the usb camera method in hailo15.
However, no matter how I test it, I still get this error: hailo15_video_create_pipeline - post event failed and returned: 1.
GST_DEBUG=3 → 0:00:00.637529720 1200 0xaaaae201a700 FIXME videodecoder gstvideodecoder.c:1193:gst_video_decoder_drain_out: Sub-class should implement drain()

First of all, I would like to ask if the USB camera is available in hailo15 and how to use it if possible.