Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Keil/AT32F402xx_v2/USB_OTG1_DEVICE/DOEPTSIZ1#0x0
OTGFS device OUT endpoint-1 transfer size register
Transfer size
Packet count
Received data PID
https://github.com/cmsis-svd/cmsis-svd-data