Hi @IniobongNkanga-8038 ,
There are many reasons for this, please try the following methods to troubleshoot this issue:
Switch to another browser, use in-private mode or clear the browser cache and try visiting the link again to see the result.
Switch to another machine/device, or switch to another network.
Check if your account has been accidentally deleted from their organization catalog.
Here are some articles you can refer to: SharePoint Online Troubleshooting: We're sorry, sign-in isn't working right now. But we're on it! Please try again later.
We’re sorry, sign-in isn’t working right now (Fix SharePoint error).
Please follow the above methods and if the problem persists, please let us know the results of your attempts.
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