Adding an External service via UI - Custom labels

Percona Monitoring and Management (PMM) Database Monitoring and Management
1

Hello,
I wonder how can I add external service, I check many options for Custom labels but any of then don’t work.
I try to find some examples in documentation

I stuck on:

Zrzut ekranu z 2023-10-31 15-51-35
Zrzut ekranu z 2023-10-31 15-51-35858×932 38 KB