I’ve been using ArduinoJson on several PlatformIO projects but hit a problem installing it in a new project. The following screenshot shows the error and the “Check Available Solutions” button suggests I report the error here:

Looking forward to a solution.
Works for me

Can you show the exact platformio.ini
of the project? Usually “Could not find the package…” indicates that the library name was miss-spelled, but I did not see that error on your screenshot…
I am using the PIO Home in the IDE to do the install not the command line. I have been able to install the previous version (16.7.3) without any problem so I’m still not sure what is wrong when I try 6.18.0. For what it’s worth, here is the platformio.ini after installing 16.7.3:
[env:nodemcu-32s]
platform = espressif32
board = nodemcu-32s
framework = espidf
monitor_speed = 115200
monitor_flags = --raw
monitor_port = /dev/cu.usbserial-0001
build_type = debug
debug_tool = esp-prog
upload_protocol = esp-prog
debug_init_break = tbreak app_main
lib_deps = bblanchon/ArduinoJson@6.17.3
When you replace this with lib_deps = bblanchon/ArduinoJson @ ^6.18.0
and recompile you get the same errror?