Different bus. place or sect. code in contract &1 for val. period &2 - &3

What causes this issue?

During a posting activity, the system checks the following settings
relating to the objects that are assigned to a contract:
Checks whether the assigned objects belong to different business places.
If the objects belong to more than one business place, the system also
checks the validity periods of the object-contract relationship because
they must not overlap in case the business places are different.
Checks whether the section codes are also correctly assigned to the
objects for the given validity periods.
You have received this error message, because one of the above checks
found an error.

System Response

The system terminates the process.

How to fix this error?

Please ensure that you have the correct business places and section
codes assigned to the relevant validity periods of the object-contract
relationship. The following <ZH>examples</> explain the requirements:
Correct Assignments:
Object,,Validity Period,,Business Place,,Section Code
O1,,01.01.2017 - 31.03.2017,,BP01,,SC01
O2,,01.01.2017 - 31.03.2017,,BP01,,SC01
O3,,01.04.2017 - 31.07.2017,,BP02,,SC02
Here the validity periods for BP01 and BP02 do not overlap, and the
section codes are correct.
Object,,Validity Period,,Business Place,,Section Code
O1,,01.01.2017 - 31.03.2017,,BP01,,SC01
O2,,01.04.2017 - 31.07.2017,,BP02,,SC02
O3,,01.04.2017 - 31.07.2017,,BP02,,SC02
Here the validity periods for BP01 and BP02 do not overlap, and the
section code assignments to validity periods is correct (one code for
one validity period).
Incorrect Assignments:
Object,,Validity Period,,Business Place,,Section Code
O1,,01.01.2017 - 31.03.2017,,BP01,,SC01
O2,,01.04.2017 - 31.07.2017,,BP02,,SC02
O3,,01.04.2017 - 31.07.2017,,BP03,,SC02
Here the validity periods for BP02 and BP03 overlap.
Object,,Validity Period,,Business Place,,Section Code
O1,,01.01.2017 - 31.03.2017,,BP01,,SC01
O2,,01.04.2017 - 31.07.2017,,BP02,,SC02
O3,,01.04.2017 - 31.07.2017,,BP02,,SC03
Here the validity periods for BP01 and BP02 do not overlap, but
different section codes are assigned to the same validity period.

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.