Hi @Trina Brown,
- Are you posting the message in a group chat or in a channel?
- Would you be able to delete other messages besides the message with attachment?
Please follow these steps to see if you can delete the message:
(the example is to delete a message in channel, which is similar in a group chat)
If you cannot see the Delete option, and you are also unable to delete other messages no matter if the messages have attachments, the cause may probably due to your account has a message policy assigned which restricts you from deleting messages.
In this case, please contact your Teams administrator to confirm it.
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