BRF+: &1 is recorded under transp. obj. &2 but not under &3; see longtext

What causes this issue?

In the current transport request, the system has determined an
inconsistency with BRFplus object '&v1&'. For objects of this type, it
is required that the object is transported with references to two
different transport objects, namely '&v2&' and '
&v3&'. However, the object on this transport is assigned to transport
object '&v2&' only, while transport object '&v3&' is missing in the
transport piece list.
BRFplus application objects need to be registered under different
transport objects in the transport piece list: For example, under
transport object FDT0 and under FDT0001 or FDT0002. These registration
entries belong semantically together, and they are maintained
automatically by BRFplus. To ensure semantic consistency, transport
piece lists created by BRFplus must not be changed manually.

System Response

The transport request cannot be exported.

How to fix this error?

Use the normal change or transport recording for BRFplus content
objects. Do not manipulate the piece lists of the transport requests
used for the change or transport recording manually.
If required, you can use report FDT_TRANS to write an already existing
BRFplus object or a whole BRFplus application to a transport request in
a consistent manner.

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.