How To Fix USMDZ3205 - &1 &2 No message type defined for message "&3" in Customizing

SAP Error Message - Details

• Message type: E = Error

• Message class: USMDZ3 - Nachrichtenklasse zum UI des User-Interfaces

• Message number: 205

• Message text: &1 &2 No message type defined for message "&3" in Customizing

What causes this issue?

No message type has been specified for the message to be issued.

System Response

In this case, the message is issued as an error message; therefore, you
may not be able to save the data.

How to fix this error?

For the stated message, specify at least the standard message type at
the top level in Customizing.
In addition, you also can define the message type for the various
checking levels at the next lower level (edition, change request, or
single maintenance).

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.