Composer giving cannot resolve to an installable set of packages because no matching package found for projects that definitely exist

In short: Make sure you haven’t deleted the Drupal repository from your composer.json or, what i did (as warned by the message that the key repositories is a duplicate!) accidentally overrode the repositories section.

$ composer update
Key repositories is a duplicate in ./composer.json at line 52
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Installation request for drupal/drutopia_core dev-8.x-1.x as 1.x-dev -> satisfiable by drupal/drutopia_core[dev-8.x-1.x].
    - drupal/drutopia_core dev-8.x-1.x requires drupal/ds ^3.7 -> no matching package found.
  Problem 2
    - drutopia/drutopia dev-8.x-1.x requires drupal/features ^3.11 -> no matching package found.
    - drutopia/drutopia dev-8.x-1.x requires drupal/features ^3.11 -> no matching package found.
    - Installation request for drutopia/drutopia dev-8.x-1.x as 1.x-dev -> satisfiable by drutopia/drutopia[dev-8.x-1.x].

Potential causes:
 - A typo in the package name
 - The package is not available in a stable-enough version according to your minimum-stability setting
   see <https://getcomposer.org/doc/04-schema.md#minimum-stability> for more details.
 - It's a private package and you forgot to add a custom repository to find it

Read <https://getcomposer.org/doc/articles/troubleshooting.md> for further common problems.
composer [update] failed, composer command failed: exit status 2. stderr=