Remove C15.

Thank you a million, yes that works!
Love a simple fix!

I've just had my first PCB design delivered from JLCPCB and it _almost_ works! :|
Apart from the various I2C & GPIO attachments, It's based around the DevkitC v4 Reference Design so I had expected it to work largely out of the box the same as my breadboarded prototype.

I can flash firmware to it ...