Reproduction steps:
1. Open the attached “Test Project” project (Use tester provided project in the comments - "IN-39626_PSBS")
2. Open the “Input Systems/CustomInputActions” Input Action Asset in the Project window
3. Select “Radar” Action Map → “Zoom” Action → “Controller Triggers” Binding
4. Change the value in “Press Point” Input to “0.1”

Expected result: The Input value is changeable
Actual result: The Input value becomes disabled and the “Default” checkbox becomes checked

Reproducible with: 1.3.0, 1.4.4, 1.5.1, 1.6.1 (2022.2.17f1, 2023.1.0b14, 2023.2.0a12)
Couldn’t test with: 2020.3.47f1, 2021.3.24f1 - “CustomInputActions” Input Action Map is not accessible

Reproducible on: Windows 10