Posting run & not yet posted. Trip cannot be changed.

What causes this issue?

A trip cannot be changed if the following applies:
The trip has accounting status 'Transferred to FI' or 'Canc.Posted to
FI'. This status is assigned to the trip as soon as it flows s
uccessfully into a posting run. This status is independent of whether
this posting run was then actually posted.
The posting run into which the trip last flowed was not posted
completely. A posting run is fully posted only if it has the status
'Documents Posted' or 'Zero Postings Posted'. Only the status of the
posting run itself is decisive. It is irrelevant whether the documents
for this trip are posted; this can be the case if the posting run has
the status 'Partially Posted'.

How to fix this error?

RESET N1
Go to posting run management and post the trip transfer documents by
posting the posting run fully.
After that, make your trip changes.

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

<ZH>Note:</>
A posting run that has the status 'Zero Posting' also has to be posted.
The status then changes to 'Zero Postings Posted'.
It may not be possible to fully post the posting run, for example, if
the posting run has the status 'Selection is running' or has the status
'Incorrect documents' or 'Partially posted'. In this case, errors in
the documents can prevent the complete posting. Instead of posting the
posting run, you have to discard it. The status of the trips is then
reset to 'Settled'. Preferably, the posting of the posting run should be
enabled, however.

Error message extract from SAP system. Copyright SAP SE.