See: https://www.dnssec-validator.cz/
https://addons.mozilla.org/pl/firefox/addon/dnssec-validator/
TLS lately has come under fire, the encryption layer between browser (device) and websites.
A solution against cybercriminal actions is formed by DANE based on DNSSEC, fundamentally new and making the Internet a more secure place to be. The website side is often OK (1.7 million sites secured), Big cablers and ISP providers are still rolling this out in places and often lack behind e.g. in European countries.
Check your situation through the DNSSEC/TLSA Validator add-on/extension.
Online you can check domains here: http://dnssec-debugger.verisignlabs.com/
Move your mouse over any symbols for remediation hints.
polonus