New serial port problem

Hi I have been using the PIO serial monitor for about a year, but now have the error shown below. Any help much appreciated:

> Executing task: C:\Users\Paul\.platformio\penv\Scripts\platformio.exe device monitor <

Error: Unknown development platform 'atmelmegaavr'
The terminal process "C:\Users\Paul\.platformio\penv\Scripts\platformio.exe 'device', 'monitor'" terminated with exit code: 1.

pio.ini (unchanged from many successful uses)

; PlatformIO Project Configuration File
;
;   Build options: build flags, source filter
;   Upload options: custom upload port, speed and extra flags
;   Library options: dependencies, extra library storages
;   Advanced options: extra scripting
;
; Please visit documentation for the other options and examples
; https://docs.platformio.org/page/projectconf.html

[env:ATmega4809]
board = ATmega4809
platform = atmelmegaavr
framework = arduino
board_build.variant = 40pin-standard
board_build.f_cpu = 20000000L
monitor_flags = 
    --echo
upload_protocol = custom
upload_speed = 115200
upload_port = COM6
upload_flags = 
    -d
    atmega4809
    -c
    $UPLOAD_PORT
    -b
    $UPLOAD_SPEED
upload_command = pyupdi $UPLOAD_FLAGS -f $SOURCE
monitor_port = COM3
monitor_speed = 19200
lib_deps = qub1750ul/SoftwareReset@^3.0.0


;upload_protocol = custom
;upload_speed = 115200
;upload_port = COM4
;upload_flags =
;  -t
;  uart
;  -d
;  $BOARD_MCU
;  -u
;  $UPLOAD_PORT
;  -c
;  $UPLOAD_SPEED
;upload_command =  pymcuprog write $UPLOAD_FLAGS -f $SOURCE


[platformio]
description = The integrated Azimuth Encoder

now also getting an error box bottom right of the ide screen which states
command ‘platformio-ide.serialMonitor’ not found

Unfortunately magic can happen - I hate magic for obvious reasons.

I have done nothing but retry my serial port a few times this morning and now it works.

So I’ll carry all the kit back to my remote location and hope it works there too :slight_smile: