Our site is learn.kodekonveyor.com it is available only on https, using a letsencrypt certificate.
I have checked everything I could (mobile app is enabled, moodle version is okay; '3.7+ (Build: 20190614)'), and the same site works with the desktop app on my computer.
The only thing I have found is that one of the ssl checkers recommended in this site says that the letsencrypt root cert is not in the certificate chain.
Does the mobile app recognize letsencrypt? Or is it depending on the mobile os (Android in this case)?
Is it the problem, or should I search further?
If the problem with letsencrypt, can I avoid somehow to use another certificate?