Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Silicon Labs/Series0/EZR32WG/EZR32WG330F128R68/USB/DIEP0TSIZ#0x0
Device IN Endpoint 0 Transfer Size Register
Transfer Size
Packet Count
https://github.com/cmsis-svd/cmsis-svd-data