Swapped an STM401 with an STM412 and having issues, JLCPCB incorrect model?

[Olligater]

As title really. Keyboard project i'm working on in QMK required a bit more RAM so upgraded from the STMf401 to an STM32F412xE. Flashed firmware onto it RGB animations and OLED work correctly but USB device not recognised by computer. STM32cubeprogrammer shows 1mb of flash memory so concerned if JLCPCB have swapped it out for another model which would potentially be incompatible or just striahgt upgraded to the xG wtihout mentioning anything? Anybody experienced anything similar?

[TDK]

What is the full part numbers of the chip you're moving from and moving to?

The part numbers are written on the package. Should be easy to read the top of the chip to see if what you ordered is what you got.

[Olligater]

Sorry for the late reply! Its an STM32F412CEU6 and i'm moving from the STM32F401CCU6

[Karl Yamashita]

Maybe I'm misinterpreting but it sounds like you just took the same FW from the STM32F401 and programmed the STM32F412? Or did you start a new project, configured the Clock, ported your code over and build again?

As for the flash size difference, does STM32Cube Programmer show enough Device information between the CE and CG, or it is showing xx?

[Tesla DeLorean]

Show the chip and USB portion of the schematic. The MCU should support USB connectivity with right circuit and firmware. 

Do you have an external crystal for HSE?

Perhaps try connecting with USB when you have BOOT0 strapped high. This should initiate the system loader at power up, check AN2606 for chip level features and pins, and if it supports USB you might expect to see "STM32 Boot Device".

This might tell you if it's wired correctly.