Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - barryvdh/laravel-debugbar is locked to version v2.3.2 and an update of this package was not requested.
s with another require.
  Problem 2
    - barryvdh/laravel-dompdf is locked to version v0.8.2 and an update of this package was not requested.
    - barryvdh/laravel-dompdf v0.8.2 requires illuminate/support 5.1.x|5.2.x|5.3.x|5.4.x|5.5.x|5.6.x -> found illuminate/support[v5.1.1, ..., v5.6.39] but these were not loaded, likely because it conflicts with another require.
  Problem 3
    - barryvdh/laravel-ide-helper is locked to version v2.3.2 and an update of this package was not requested.
    - barryvdh/laravel-ide-helper v2.3.2 requires illuminate/console ^5.0,<5.5 -> found illuminate/console[v5.0.0, ..., v5.4.36] but these were not loaded, likely because it conflicts with another require.
  Problem 4
    - kyslik/column-sortable is locked to version 5.4.11 and an update of this package was not requested.
ire.
    - laravelcollective/html is locked to version v5.4.9 and an update of this package was not requested.
  Problem 6
    - nwidart/laravel-menus is locked to version 0.5.0 and an update of this package was not requested.
    - nwidart/laravel-menus 0.5.0 requires illuminate/config 5.4.* -> found illuminate/config[v5.4.0, ..., v5.4.36] but these were not loaded, likely because it conflicts with another require.
  Problem 7
    - nwidart/laravel-modules is locked to version 1.27.2 and an update of this package was not requested.
re (5.8.0).
  Problem 8
    - sofa/eloquence is locked to version 5.4.1 and an update of this package was not requested.
    - sofa/eloquence 5.4.1 requires illuminate/database 5.4.* -> found illuminate/database[v5.4.0, ..., v5.4.36] but these were not loaded, likely because it conflicts with another require.

has raised this errors it tried to install each package seperatly but still didnt work.
can anyone help me through this.

>Solution :

Try reinstalling the packages. remove all and install them again