Can't Launch/Package/Cook my game

Hello everyone I can’t launch my game from the editor of Unreal Engine version 4.20 when I press the launch button…
The launcher compile assets and deploying to the desktop but no game is launched and it say “Launch completed”
I don’t understand why can you help me please i have to work hurry. Thanks for your answer.

LogCook: Display: Cook by the book total time in tick 0.000367s total time 7.479503
LogCook: Display: Peak Used virtual 7254 Peak Used phsical 6080
LogCook: Display: Hierarchy Timer Information:
LogCook: Display: Root: 0.000000ms
LogCook: Display: StartCookByTheBookTime: 4541.490894ms
LogCook: Display: CleanSandboxTime: 2785.841035ms
LogCook: Display: CollectFilesToCook: 192.243285ms
LogCook: Display: CookModificationDelegate: 0.006566ms
LogCook: Display: SearchForPackageOnDisk: 0.002189ms
LogCook: Display: GetObjectsWithOuter: 0.047043ms
LogCook: Display: GeneratePackageNames: 0.219898ms
LogCook: Display: UnsolicitedPackageAlreadyCooked: 0.192912ms
LogCook: Display: PackageCast: 0.047991ms
LogCook: Display: FullGCAssetsContains: 0.016274ms
LogCook: Display: AddUnassignedPackageToManifest: 0.000000ms
LogCook: Display: GetCachedName: 0.059323ms
LogCook: Display: AddToPackageList: 0.000000ms
LogCook: Display: GenerateLongPackageName: 0.075487ms
LogCook: Display: SavingCurrentIniSettings: 66.866213ms
LogCook: Display: ProcessingAccessedStrings: 21.005459ms
LogCook: Display: SavingAssetRegistry: 2825.555978ms
LogCook: Display: BuildChunkManifest: 542.641805ms
LogCook: Display: SaveManifests: 3.760153ms
LogCook: Display: SaveRealAssetRegistry: 2029.160265ms
LogCook: Display: WriteCookerOpenOrder: 248.816654ms
LogCook: Display: IntStats:
LogCook: Display: LoadPackage=20
LogCook: Display: SavedPackage=603
LogPlayLevel: Completed Launch On Stage: Cooking in the editor, Time: 2.014864
LogPlayLevel: Completed Launch On Stage: Build Task, Time: 0.272230
LogPlayLevel: Completed Launch On Stage: Deploy Task, Time: 0.000043
LogPlayLevel: Completed Launch On Stage: Run Task, Time: 0.000056
LogPlayLevel: Completed Launch On Stage: Post Launch Task, Time: 0.000007
LogPlayLevel: Launch On Completed. Time: 5.282737