How To Fix AP261 - Plan values exist - assignment not possible due to planning lock

AP261 - Overview

• Message type: E = Error

• Message class: AP - Investment program messages

• Message number: 261

• Message text: Plan values exist - assignment not possible due to planning lock

What causes this issue?

You tried to assign a measure (or an appropriation request) to a
program position of investment program &V1&/&V2& that has program type
&V4&.
However, there is a planning lock for planning measures (or
appropriation requests) for version &V3& of an investment program of
approval year &V2& and program type &V4&. This means that the total of
the plan values from the assigned measures and appropriation requests
for version &V3& on this investment program is not allowed to change.
But if you assign the measure (or appropriation request), the plan
value would change, since the measure (or request) has plan values for
version &V3&.

System Response

The assignment is not allowed.

How to fix this error?

Reduce the plan value of the measure (or appropriation request) in
version &V3& to zero.
If this error occurred during processing of an appropriation request,
when the request was replaced by a measure, then check all measures
assigned to the appropriation request in version &V3&, and reduce their
plan values to zero.

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.

AP261 - Details

• The SAP error message AP261 ("Plan values exist - assignment not possible due to planning lock") typically occurs in the context of planning and budgeting within SAP, particularly in modules like SAP Controlling (CO) or SAP Project System (PS). This error indicates that there are existing planning values for a particular object (like a cost center, internal order, or project) that are preventing further assignments or changes due to a planning lock.
  
  Cause:
  
  Existing Plan Values: The primary cause of this error is that there are already planned values for the object you are trying to assign or modify. This means that the system has locked the planning data to prevent inconsistencies.
  Planning Lock: The planning lock is a mechanism in SAP that prevents changes to planning data while it is being processed or if it has already been set.
  Concurrent Users: If multiple users are trying to access or modify the same planning