Hi @Sanjay ,
I tried testing in my lab tenant and can reproduce the issue you described, regardless of whether the account I used to login OWA is an owner or a member of this Office 365 group:
I've checked it using Exchange Online PowerShell and can verify that Connectors feature is enabled in my tenant and also for the group:
Then I tried searching around but so far haven't found any relevant official articles about this issue. Given this situation, I'd recommend contacting Office 365 business support via the M365 admin portal for further assistance with this issue. (Note: This requires an admin account, if you get a message that says you don't have the permission, please report it to your M365 administrator first.)
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.