Planning data integration not possible for version &/&/&

What causes this issue?

The planning data integration cannot be activated for the specified
plan version.
Reason: plan line items have already been written, but an opening
balance for the line items has not yet been created. The total of the
summary records and plan line items can therefore differ.

How to fix this error?

There are two possibilities:
Use a different plan version.
Proceed as follows:
Create a new plan version, for example, 'SAV' (Save version).
<DS:TRAN.KP91>Proceed</>
Copy version &V3& to version 'SAV' using the 'Copy planning'
transaction.
<DS:TRAN.KP97>Proceed</>
Delete all planning data of version &V3& for controlling area
&V1& in fiscal year &V2& using the 'Archive planning data of cost
centers' program.
<DS:TRAN.OKE3>Proceed</>
Set the integration indicator for version &V1&/&V2&/&V3& using the
'Change plan version' transaction.
<DS:TRAN.KP92>Proceed</>
Copy version 'SAV' to version &V3& using the 'Copy planning'
transaction.
<DS:TRAN.KP97>Proceed</>

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