Octoprint firmware update SKR v1.4 tx/rx connection

What is the problem?
I try to update the firmware of my SKR 1.4 trought rx/tx connection and usbmount/flash firmware.

What did you already try to solve it?
I've follow this guide to connect the board to Octoprint.
I've try this solution, this one too to try to mount the sd card.

Logs (octoprint.log, serial.log or output on terminal tab at a minimum, browser error console if UI issue ... no logs, no support!)
octoprint.log (495.1 KB)

Additional information about your setup (OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible)

I can connect OP to my board and control it but I cant mount the sd card to make the firmware update.

OP > Version 1.4.0

Marlin 2.0 settings for a working RX/TX connection Between SKR V1.4 and PI4 with Octoprint.

Marlin serial port selection :
#define SERIAL_PORT 0
#define SERIAL_PORT_2 -1

Which firmware and version are you using? Recent issues I've seen in other posts seemed to be resolved with updating Marlin to the latest 2.0 bugfix branch and I wonder if that would make any difference.

I've re-upload the marlin bugfix newest file and that doesn't work.

You'd have to know which one you downloaded, the bugfix branches aren't distributed as releases if I remember correctly.

Yeah I have upload the bug fix version.