No valid sender entries exist

What causes this issue?

You have specified a sender area by entering single values (from-to) or
group names in the selection criteria. The SAP System has checked the
master data and no valid senders exist in the area you specified.

System Response

The SAP System does not switch to the single value entry screen.

How to fix this error?

Check your entries for the selection criteria. Another possibility is
that the master data is locked. You can access additional information
with the "Error log" function.

Error message extract from SAP system. Copyright SAP SE.