RAISE EXCEPTION with incorrect message type in &1 include &2 line &3

What causes this issue?

A RAISE EXCEPTION was triggered but the message type is neither 'A'
(termination) or 'E' (error).

System Response

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

How to fix this error?

Procedure for System Administrators

In program &1 include &2 line &3, change the RAISE EXCEPTION statement.
You have three options:
You want to work without a message, only using the TEXTID of the
exception class. In the RAISE EXCEPTION, do not transfer any parameters
except (optional) TEXTID. The system interprets the exception as an
error message.
You want to issue an error message. In this case, transfer parameter
M_MSGTY = 'E' for the RAISE EXCEPTION.
You want to issue a warning. In this case, RAISE EXCEPTION is the wrong
statement. Use the following statement:
DATA: l_refo_badi TYPE REF TO /LIME/CX_BADI,
l_message TYPE bapiret2-message.
* Replace xxx by message number and yy by message id
MESSAGE Wxxx(yy) INTO l_message.
CREATE OBJECT l_refo_badi
EXPORTING m_msgty = sy-msgty
m_msgno = sy-msgno
m_msgid = sy-msgid
* m_v1 = sy-msgv1
m_msgtx = l_message.

Error message extract from SAP system. Copyright SAP SE.