Why sometimes ssl fails to verify when accessing a site?

Question

Digital certificates

everything is ok on the PC, but sometimes when you log in from a mobile https it lights up red, it says it was not possible to check. Now I'm ok. Saygood.ru from mobile

Answer 1

tls1.2 is enabled on the server side, which supports modern encryption algorithms. Mobile software is apparently not such fashionable software, and does not know how to tls1.2.
for compatibility with old browsers, you need to enable tls1 tls1.1 on the server side
only sslv2 sslv3 below. but it's not safe

Answer 2

https://www.ssllabs.com/ssltest/analyze.html?d=say...
we look, we fix problems