When you assign a Sales Unit XYZ to any Sales documents like Sales Order, Service Order, Leads or Opportunities, system throws below error message:
Sales organization for sales unit XYZ missing in master data
There is no Sales Organization exist for Sales Unit XYZ.
Because, when you assign a Sales Unit to a sales documents, system should find a Sales Organization. Which means, there should be a Sales Organization for the Org Unit XYZ in the same hierarchy above it or the Org unit XYZ itself can be a Sales Organization.
To overcome the issue, you can either make the Org Unit XYZ as a Sales Organization or any Org Unit which is above the hierarchy.
KBA , AP-BP-BPT , Business Partner Template , Product Enhancement