Restore the composer.lock file from your version control system that was used before you updated.
The composer.lock exactly records which software was installed. So it is paramount to commit this file into version control in order to be able to go back to a working version in case of update failure.
Running composer install will always install the software ...
myparcelnl/magento module is compatible with 2.4.x.
I think issue in your composer.josn file. You need to update composer.json file,
edit composer.josn file from your Magento's root path
Step-1: Change version
"version": "2.x.x" with "version": "2.4.2",
Step-2: Update version under require,
If you find yourself in this situation like I did it's possible you skipped the step in the cli upgrade process to update the additional packages. Please see the dev docs links:
In short the step "Specify Additional Packages" is what I missed which would've updated the additional ...
Use composer self-update --update-keys to update pubkeys.
Enter Dev / Snapshot Public Key (including lines with -----):
-----BEGIN PUBLIC KEY-----
It appears that this error might appear when a MySQL database is empty, but the env.php file is present. (Possibly because you had setup Magento, but for some reason, database was deleted.)
To fix this you can add --cleanup-database flag to setup:install command (For me, it went ok only after the second try.), or delete the env.php file indeed, which I don't ...