Sandisk SSD not showing up on iPhone 14 ProMax Files

hiya. i news to export photos directly from my phone onto my Sandisk SSD external hard drive. to do this i:

1) Attached a "Lightning to USB 3 Camera Adapter" to my IPhone with lightening - USBC

2) Then plugged a charger adapter into the other USBC port

3) Then I attached the external drive via the USB port to the adapter.

The disk is not showing up on my files, my phone isn’t charging either - I’m not sure if that means the adapter isn’t working or if it isn’t supposed to charge whilst its

connected to a hard drive- but since it’s plugged in to a socket I figure I should mention I’m not seeing signs of power. Really just don’t know what to do I need to upload directly from my iPhone 14 to the external drive please help