Since files saved on Teams are saved in OneDrive or SharePoint. What you can do is to locate the file you shared with the participants. Click on the 3 dots beside the files and select manage access >>> Links >>> click on stop sharing. With that the person that have access to this link before wont have access again.
Please check this link: https://support.microsoft.com/en-us/office/share-sharepoint-files-or-folders-1fe37332-0f9a-4719-970e-d2578da4941c