i accidently delete the chat in a person chat yesterday

Hi @Amaldass Augustin, 

Welcome to the Q&A Community 

I’m here to assist your problem. 

Could you please provide more information to me for a better support: 

• You are using Business account or Personal Account ? 
• You are Admin user or Non-admin user ? 

In the meantime, please confirm if you are using Personal account. .
If you are using Business account, I recommend you for two options below : 

Non-admin users: 

A non-admin user cannot restore a deleted chat or message. Your best option is to ask the person(s) you were chatting with to copy and paste the conversation history to you. Since deleting a chat only removes it from your own view, they will still have the full history. 

If you deleted individual messages, they are permanently gone for everyone in the chat. The only way to retrieve them is to contact an administrator. 

Admin Users:

A Microsoft 365 administrator can restore deleted messages, but not a deleted chat. An admin can recover individual messages using the eDiscovery tool in the Microsoft Purview compliance portal. This is only possible if a compliance retention policy was in place for Teams messages before they were deleted. Refer to : Overview of security and compliance - Microsoft Teams | Microsoft Learn 

Office 365 global admin can try to use the Office 365 Content Search to get the details about the Chat history in Teams and then export the search results to check them. 

1.Go to the Microsoft Purview compliance portal and sign in using the credentials of an account that's been assigned the appropriate permissions. 

2.In the left navigation pane of the compliance portal, select Content search. 

3.On the Content search page, select Create a search. 

4.On the Name and description page, enter a name for the search, an optional description that helps identify the search. The name of the search must be unique in your organization. 

5.On the Data Sources , choose the content locations that you want to search. You can search mailboxes, sites.

6.On the Conditions page, enter a keyword query and add conditions to the search query if necessary. 

Specify keywords, message properties such as sent and received dates, or document properties such as file names or the date that a document was last changed. You can use more complex queries that use a Boolean operator, such as AND, OR, NOT, and NEAR. If you leave the keyword box empty, all content located in the specified content locations is included in the search results. For more information, see Keyword queries and search conditions for eDiscovery. 

You can add search conditions to narrow a search and return a more refined set of results. Each condition adds a clause to the search query that is created and run when you start the search. A condition is logically connected to the keyword query (specified in the keyword box) by a logical operator (c:c) that is similar in functionality to the AND operator. That means that items have to satisfy both the keyword query and one or more conditions to be included in the results. This is how conditions help to narrow your results. For a list and description of conditions that you can use in a search query, see Search conditions. 

Review the search settings (and edit if necessary), and then select Submit to start the search. 

You can refer to: Search for and delete chat messages in Teams | Microsoft Learn 

Recovering MS Teams messages | Microsoft Community Hub 

We appreciate your kind patience and understanding that sometimes the initial response may not immediately resolve the issue or there may be some misunderstandings about your scenario, but we would love to hear updates from you and find out further suggestions. 

Thank you for your kindness and understanding. If you need anything else, please feel free to contact me.  

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