Installation failed

[gotoin]

  Problem 1
    - Installation request for moon/artisan ^1.9 -> satisfiable by moon/artisan[v1.9].
    - Conclusion: remove symfony/console v2.8.31
    - Conclusion: don't install symfony/console v2.8.31
    - moon/artisan v1.9 requires illuminate/console 5.5.* -> satisfiable by illuminate/console[v5.5.0, v5.5.16, v5.5.17, v5.5.2].
    - illuminate/console v5.5.0 requires symfony/console ~3.3 -> satisfiable by symfony/console[v3.3.0, v3.3.1, v3.3.10, v3.3.11, v3.3.12, v3.3.13, v3.3.2, v3.3.3, v3.3.4, v3.3.5, v3.3.6, v3.3.7, v3.3.8, v3.3.9].
    - illuminate/console v5.5.16 requires symfony/console ~3.3 -> satisfiable by symfony/console[v3.3.0, v3.3.1, v3.3.10, v3.3.11, v3.3.12, v3.3.13, v3.3.2, v3.3.3, v3.3.4, v3.3.5, v3.3.6, v3.3.7, v3.3.8, v3.3.9].
    - illuminate/console v5.5.17 requires symfony/console ~3.3 -> satisfiable by symfony/console[v3.3.0, v3.3.1, v3.3.10, v3.3.11, v3.3.12, v3.3.13, v3.3.2, v3.3.3, v3.3.4, v3.3.5, v3.3.6, v3.3.7, v3.3.8, v3.3.9].
    - illuminate/console v5.5.2 requires symfony/console ~3.3 -> satisfiable by symfony/console[v3.3.0, v3.3.1, v3.3.10, v3.3.11, v3.3.12, v3.3.13, v3.3.2, v3.3.3, v3.3.4, v3.3.5, v3.3.6, v3.3.7, v3.3.8, v3.3.9].
    - Can only install one of: symfony/console[v3.3.0, v2.8.31].
    - Can only install one of: symfony/console[v3.3.1, v2.8.31].
    - Can only install one of: symfony/console[v3.3.10, v2.8.31].
    - Can only install one of: symfony/console[v3.3.11, v2.8.31].
    - Can only install one of: symfony/console[v3.3.12, v2.8.31].
    - Can only install one of: symfony/console[v3.3.13, v2.8.31].
    - Can only install one of: symfony/console[v3.3.2, v2.8.31].
    - Can only install one of: symfony/console[v3.3.3, v2.8.31].
    - Can only install one of: symfony/console[v3.3.4, v2.8.31].
    - Can only install one of: symfony/console[v3.3.5, v2.8.31].
    - Can only install one of: symfony/console[v3.3.6, v2.8.31].
    - Can only install one of: symfony/console[v3.3.7, v2.8.31].
    - Can only install one of: symfony/console[v3.3.8, v2.8.31].
    - Can only install one of: symfony/console[v3.3.9, v2.8.31].
    - Installation request for symfony/console (locked at v2.8.31) -> satisfiable by symfony/console[v2.8.31].

thanks.

[segadora]

Paste your composer file.