Deleting All Lines on Requisition - No Warning Message Displayed in RSSP

Problem Statement:
In RSSP, when a requisition contains only a single line and the user cancels that line, the entire requisition gets cancelled automatically. As a result, the requisition number is lost, and users must create a new requisition if they want to add new lines.

Behavior in RSSP:

Single-line requisition → cancel the line → requisition is cancelled silently, no warning message
Requisition number disappears
User must create a new requisition, which breaks the linkage on the other P2P documents which were linked to the Original PR

Gap / Limitation:
Unlike the Classic Self Service Requisition page, RSSP does not provide any warning message before cancelling the only active line.