Convert errors into HttpException calls

app/Services/FlightService.php

@@ -145,7 +145,7 @@ class FlightService extends BaseService
             $user_bids = UserBid::where(['user_id' => $user->id])->first();
             if($user_bids) {
                 Log::info('User "' . $user->id . '" already has bids, skipping');
-                return null;
+                throw new BidExists();
             }
         }
 

app/Services/UserService.php

@@ -21,6 +21,7 @@ class UserService extends BaseService
 
     /**
      * UserService constructor.
+     * @param AircraftRepository $aircraftRepo
      * @param SubfleetRepository $subfleetRepo
      */
     public function __construct(