Cannot verify server identity pops up when internet is off

When i for example, leave my house and I don’t have internet anymore, a pop up called ‘cannot verify server identity’ and ‘the identity of “m.hotmail.com” cannot be verified.’ Under it shows up and I have to close it a few times because it reappears over and over again until it eventually stops. I’m not sure if this is the reason I can’t use some apps without internet when I should be able too, but either way I’d like for it to go away.