Create group using Office365 unified API returns 201 but doesn't work -

i using office365 unified apis preview deal office 365 groups, getting user groups endpoints works fine , returns user groups.

when call create group endpoint, retruns 201.created group doesn't exist in office portal nor groups api call.

here endpoint url: https://graph.microsoft.com/beta/{my_tenant_name}/groups

i landed working solution.

if trying create group, need add directory permission (unfortunately need admin consent):

read , write directory data 

these weird behaviors office365 unified apis, should excuse apis can see "beta" inside endpoint url.