Planner create API with Group Id is not working

I am creating a Planner with Planner create API. For business reason I also have to create a new group and create the planner under the new group. It was working fine until the new Planner update. Now even though I am supplying the groupId, the planner does not create under it and the group members can not access it. Is there any work around for this?

Here is how I am creating a planner,

PlannerPlan requestBody = new()

{

Container = new PlannerPlanContainer

{

Url = $"https://graph.microsoft.com/v1.0/groups/{groupId}",

},

Title = title,

};

var result = await _graphServiceClient.Planner.Plans.PostAsync(requestBody);