Tests failed on Install Dependencies

[realbudgie]

Install Dependencies
Run composer install -q --no-ansi --no-interaction --no-scripts --no-progress --prefer-dist
Your lock file does not contain a compatible set of packages. Please run composer update.
Error: Process completed with exit code 2.

I've tried composer install and composer update both with and without the mentioned flags but it says, 'Nothing to install, update or remove'.