Problem with a certificate from HOTMAIL.

Hi there, Oscar!

Thanks for visiting the Apple Support Communities. We understand you're having trouble with your Hotmail email after updating the iOS software on your iPhone. We'd be happy to help!

To get started, please use the troubleshooting found in the following Apple Support articles:

If you can’t send email on your iPhone, iPad, or iPod touch - Apple Support

If you can't receive email on your iPhone, iPad, or iPod touch - Apple Support

Don't hesitate to respond back if you still need help. If you do, please include some additional information, including:

• The exact message you receive (please do not paraphrase).
• The current iOS version installed on your phone. Example: iOS 14.4.1. You can get this under Settings > General > About > Version.
• Are you using the iOS Mail app to access your email, a third party app, or the Safari internet browser?

Best!