API Get Groups - Problem with filter

Hello,

I use this command to get a specific workspace but it doesn’t work because it gives me all my workspaces.

How do I get the filter to work?

Invoke-PowerBIRestMethod -Url "https://api.powerbi.com/v1.0/myorg/groups?$filter=$filter=contains(name,'WKS TEST Azure Pipeline')" -Method Get

what is the $filter here ? what value that variable contains ?