Reproduction steps:
1. Open the user’s attached project (“IAP Button Issue.zip“)
2. In Hierarchy select “IAP Button 1” GameObject under “Canvas”
3. Make sure that “Example_Item_1” is selected as the Product ID under the IAP Button Component in the Inspector window
4. Select “IAP Button 2” GameObject in the Hierarchy
5. Make sure that “Example_Item_2” is selected as the Product ID under the IAP Button Component in the Inspector window
6. In Hierarchy select the “IAP Button 1” and Shift + Click “IAP Button 2”
7. In Hierarchy select “IAP Button 1”
8. Observe the Product ID field

Expected result: The Product ID is set to “Example_Item_1”
Actual result: The Product ID is set to “Example_Item_2”

Reproducible with: 2021.2.0a21, 2021.3.12f1, 2022.1.21f1, 2022.2.0b13, 2023.1.0a17
Not reproducible with: 2020.3.41f1, 2021.1.25f1
Could not test with: 2021.2.0a1 - 2021.2.0a20 (PlayerLauncher.cs(169,26): error CS1061: 'BuildPlayerOptions' does not contain a definition for 'subtarget' and no accessible extension method 'subtarget' accepting a first argument of type 'BuildPlayerOptions')

Reproduced on: Windows 10 Enterprise 21H2