The below images are from the PC desktop version of Teams, menu layout may differ slightly depending on the version of Teams you are using.
Issue: Dates in files (particularly Excel) are showing in American date format MM/DD/YY instead of Australian date format DD/MM/YY
Solution: Regional Settings for the Private Channel need to be changed from USA to Australia
The date format for new private channels defaults to US, and due to how private channels operate this needs to be update for Private Channels separately.
You will need to be the Owner of a Private Channel to make the below change
Open Teams and navigate to the
Files tab of the Private Channel you need to update, then click on Open in
This should open a new Tab or Window in your browser and;
1) If you are already logged into Office 365 take your directly to the SharePoint Page
2) Bring you to the Office 365 login screen - enter your account (or select from the list) and then click Next, when prompted enter your password
When logged in you should see a screen similar to the below confirming you are on the Private Channel SharePoint page
In the top right, there is a Cog/Gear symbol next to your name called Settings click on this
Click on Site Contents then on the next screen click on Site setting on the right hand side of the screen
On the next screen click on
Regional settings listed under
You will need to change the
Locale from English (United States) to
English (Australia) then scroll down and click
OK at the bottom of the page
This will bring you back to the Site Settings page - you can now close this Tab or Window.
The date formats in your document should now be in the correct date format.