One request is already being processed for this data transfer process

What causes this issue?

You want to generate a request using data transfer process &v2&.
Request &v1& is currently being processed for this data transfer
process. No new request can be started with this data transfer process
at this time.

System Response

This action has been cancelled.

How to fix this error?

Wait until the system has finished processing the request with ID &v1&.
Use the request monitor to check the current status of the request.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.