Uf2conv build uf2 File for RPI Pico?

Hi,
tryed to build a uf2 File for RPI Pico
but did not work

Example uf2 file:

$ file picopac.uf2
picopac.uf2: UF2 firmware image, family Raspberry Pi RP2040, address 0x10000000, 687 total blocks

My File:

uf2conv target/thumbv6m-none-eabi/release/myprog -b 0x10000000 --output pico.uf2
or
uf2conv -f "Raspberry Pi RP2040" target/thumbv6m-none-eabi/release/myprog -b 0x10000000 -o pico2.uf2

file pico.uf2
pico.uf2: UF2 firmware image, file size 00000000, address 0x10000000, 4599 total blocks

What did I wrong ?

File Size is 4 MB but the flash is 2 MB as far as I know

I've not used uf2conv, but efl2uf2 works flawlessly for the rpi pico.

@nerditation

thanks a lot !
that works for me !