Error: "BMXAA7968E -- A unique key error" reported in the Configuration Tool

Symptom

Configuration Tool shows the error below:

ERROR: BMXAA7025E -- Script failed while running.;
BMXAA7968E -- A unique key error with index SKDPROPERTY_NDX2 is defined
on table skdproperty, columns (PROPERTYNAME, SKDOBJECTNAME).;
Cannot insert duplicate key row in object 'dbo.skdproperty' with unique
index 'skdproperty_ndx2'. The duplicate key value is (TARGSTARTTIME,
SKDACTIVITY).

Below is another error from running the configuration tool:

ERROR: BMXAA7025E -- Script failed while running.;

BMXAA8313E -- A statement failed to execute inside a freeform statement.
See the nested exception.;

BMXAA7968E -- A unique key error with index SKDPROPERTYMA_NDX1 is
defined on table skdpropertymap, columns (PROPERTYNAME, OBJECTNAME,
SKDOBJECTNAME).;

Cannot insert duplicate key row in object 'dbo.skdpropertymap' with
unique index 'skdpropertyma_ndx1'. The duplicate key value is
(TARGSTARTTIME, PM, SKDACTIVITY).

Caused by: BMXAA8313E -- A statement failed to execute inside a freeform
statement. See the nested exception.;

Apply Deployment Operations-CTGIN2254I: The ExecTask
runUpdateDB did not complete successfully.