How To Fix VN133 - Program & does not contain FORM routines

VN133 - Overview

• Message type: E = Error

• Message class: VN - Nachrichtensteuerung

• Message number: 133

• Message text: Program & does not contain FORM routines

What causes this issue?

The program you have entered has no FORM routine.

System Response

In this case, the system only gives a warning message which you should
observe. If you enter an incorrect program or FORM routine here, no
parameters or text variables will be replaced. In addition, you will
not be able to alter the change indicator or run a program to determine
the output issue date.
Program RSNAST00 (RSNASTOSO) ignores the warning message generated by
the incorrect entry so that processing can continue and the posting can
be made.

How to fix this error?

Please correct your entries. Check whether the problem is due to a
typing error.
Maintain a valid program that facilitates the functions described
above.

Error message extract from SAP system. Copyright SAP SE.

VN133 - Details

• SAP Error Message:
  VN133 - Program & does not contain FORM routines
  
  
  Cause:
  This error occurs when a program (usually a module pool or a report) is expected to contain certain FORM routines (subroutines), but these routines are missing. The message typically appears during runtime or activation when the system tries to call a FORM routine that does not exist in the specified program.
  In the context of SAP, FORM routines are modular blocks of code defined using the FORM ... ENDFORM statements. If a function module, screen flow logic, or another program calls a FORM routine that is not implemented in the program, the system raises this error.
  
  Common Scenarios:
  
  A screen flow logic (e.g., PBO/PAI modules) calls a FORM routine that is not defined.
  A function module or another program calls a FORM routine in a program that does not exist.
  The FORM routine was deleted or renamed but the call was not updated.
  The program was