diff --git a/plugins/modules/system_service.py b/plugins/modules/system_service.py
index 726dc74..6d824e2 100644
--- a/plugins/modules/system_service.py
+++ b/plugins/modules/system_service.py
@@ -31,18 +31,19 @@ class Module(SystemdUnitModule, SystemdReloadMixin):
                 "notify and notify-reload notify systemd about the start up via sd_notify. notify-reload needs also inform systemd on reloads and when it is ready again after an reload.\n"
                 "idle is similar to simple, but it can delay the start up by a few seconds.",
             ),
-            pre=Types.list(str, help="command or list of commands that are started before the main command(Types.str)"),
+            pre=Types.list(elements=str, help="command or list of commands that are started before the main command"),
             start=Types.list(
-                str,
-                True,
+                elements=str,
+                required=True,
                 help="command or list of commands that are started as main programm. Multiple commands are only allowed in a oneshot command",
             ),
             post=Types.list(str, help="Command or list of commands that are started after the main command(s) stopped without problems."),
             environmentfile=Types.list(
-                str, help="List of file that are containing environment variables. They are evaluated before each pre/start/post command"
+                elements=str,
+                help="List of file that are containing environment variables. They are evaluated before each pre/start/post command",
             ),
             environment=Types.list(
-                Types.dict(
+                elements=Types.dict(
                     name=Types.str(help="name of the Environment variable", required=True),
                     value=Types.str(help="value of the Environment variable", required=True),
                 ),