Switch PARALLEL_VAL (FI-AA (New)) cannot be activated

What causes this issue?

New Asset Accounting (Customizing switch <AB>PARALLEL_VAL</>) <ZH>cannot
</> be activated.
You cannot activate new Asset Accounting until the Customizing switch
has the status <LS>In Preparation</> and the Customizing settings were
made correctly.

System Response

The system does not allow you to set the Customizing switch <AB>
PARALLEL_VAL</> to <LS>Active</>.

How to fix this error?

Proceed as follows:
Set the Customizing switch for new Asset Accounting (<AB>PARALLEL_VAL</>
) to <LS>In Preparation</>.
Make the Customizing settings for new Asset Accounting.
Set the Customizing switch from <LS>In Preparation</> to <LS>Active</>.
The system then allows posting using the new posting logic.

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.