Browser blocking QFinder Pro with site not secure.

As above cannot access NAS via QFinder Pro browsers indicate insecure site. Ok yesterday not today.

What client OS and what NAS (+OS)?

windows 11 , latest qts on TS-216G .

Please always give a version number..“latest” can change daily and is bogus

Can be ignored and bypassed, in some cases
https://www.qnap.com/en/how-to/faq/article/why-does-my-nas-warn-me-that-my-connection-is-not-private