If Office 365 works on your mobile hotspot but not your home network suggests an issue specific to your home network configuration.
Windows 10 has a built-in troubleshooter that can diagnose and fix common network connection issues. Here's how to run it:
Open Settings
Go to "Network & Internet."
Click on "Status" from the left pane.
Under "Change your network settings," click on "Network troubleshooter."
Follow the on-screen instructions to complete the troubleshooting process.
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Outdated network drivers can sometimes cause connection problems. Update related driver.
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Make sure Firewall or AV is not blocking.