I was messing around with the group API both in a code editor and the testing bit (Groups Api) and it seems the API is down? It gave me the following error: 
I can’t post a bug report but I’d love it if any of you could maybe test to make sure it isn’t down 
I have fixed this by using v1 instead, it works still but is just an older version
Response code 200 for me, all good
Weird, it is still 403 for me. I tried the group wall endpoint and it worked. It seems to just be the group info one.
Yup. Me too
At least it wasn’t just me. I’ve used v1 instead as v1 is working.
What is the API you are using?
https://groups.roblox.com/v1/groups?groupIds=3650991
does not seem right.
I was using https://groups.roblox.com/v2/groups?groupIds=9554446
Sorry: just seen what you actually meant. I am now using https://groups.roblox.com/v1/groups/9554446
I meant the v1 api that you said works
did you mean https://groups.roblox.com/v1/groups/3650991