User &1 is not involved in request &2

What causes this issue?

You have selected the request &V2& (user &V1&). However, you are not
assigned to request &V2& as a user.

System Response

You cannot use request &V2&.

How to fix this error?

You have the following options:
Choose a request that belongs to you.
Choose <LS>Own requests</> from the request screen to display a list of
all requests belonging to you, or for which you are assigned to a task.
You can select one of these requests.
Choose a request for which you are assigned to a task.
Create a task in request &V2&.
In the request overview of the Transport Organizer (Transaction
<DS:TRAN.SE09>SE09</>) you can display all requests of the user &V3&.
User &V3& is responsible for the request &V2&.
Choose <LS>Add user</> to add yourself to request &V2& as a user.
If you do not have the authorization to do this yourself, contact the
user responsible for the request, &V3&.

Error message extract from SAP system. Copyright SAP SE.