Overview
Expected Effect
For data in a column where the values are displayed in a list, if adjacent cells contain identical values (which are considered errors), the background of the cells should be highlighted, as shown in the following figure.

Implementation Method
You can use hierarchical coordinate formulas in Condition Attribute to get the values of the cells above and below the current cell. If the current cell value is the same as the previous or next cell value, the background color of the current cell is red.
Example
Data Preparation
Create a general report and create a built-in dataset, as shown in the following figure.

Table Design
Drag the data columns into the cells respectively, and design the table as shown in the following figure.

Select List in Data Setting for cell A1, as shown in the following figure.

Condition Attribute Adding
Select cell A1, add a condition attribute, select Background from the attribute drop-down list, click Edit to select a color, and select Current Cell from the drop-down list. Set Common Condition to Common, and add two conditions, and currentValue Equal to '=A1[A1:+1]' and or currentValue Equal to '=A1[A1:-1]'. The two conditions are connected by OR.
The description of the formula:
A1[A1:+1]: To get the value of the cell immediately below the current cell.
A1[A1:-1]: To get the value of the cell immediately above the current cell.
Note:The following figure shows the steps.

Effect Display
PC
Save the report and click Pagination Preview. The effect is the same as that shown in section "Expected Effect."
Mobile Terminal
The template can be previewed on both the DataAnalyst app and the HTML5 terminal. The following figure shows the effect.

Template Download
For details, you can download the template Highlighted Background Colors for Duplicate Values in Adjacent Cells.cpt.