@Hawkins Samantha Based on your post we understand that when we deleted the message, deleted message appeared as "This message has been deleted" (as per below screenshot) and you want to remove this space or want to permanently delete message.
We understand your requirement that it will reserve space in your chat but for "This message has been deleted", we have only one option available and its “Undo”. Many times accidently users are deleted message and they wants to recover it, so at this moment our Product Teams has only set “Undo” option for recover message. But your suggestion is also very useful and we appreciate for your valuable suggestion.
To get this feature, we recommend you give you suggestions in Teams UserVoice.Many features of our current products are designed and upgraded based on customers’ feedback. With requirements like this increase, the problem may well be released in the future. Thanks for your understanding and support.
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