Reset functionality is not working on App Store Settings (Preset)

Steps to Reproduce:

1. Create a new Project
2. Install, Package manager > Unity Distribution Portal
3. Windows > UDP > Settings > Create Preset of the UDP Settings
4. Click on Add new IAP and enter details of the IAP
5. Click on App Store Settings > burger button > Reset

Expected Result:
Values should be cleared

Actual Result:
Values are not cleared

Reproducible on: 2020.2.0a5, 2020.1.0b4, 2019.3.7f1, 2019.2. 12f1, 2019.1.14f1, 2018.4.17f1

Environment: Windows 10 and Mac 10.14