Some older Android devices are getting "could not connect" errors when running the Warzone Android app starting yesterday.
I have made a new version of the Android app (version 188.8.131.52) that works around this issue, and I've sent it to Google for immediate publishing. However, it can take 1-2 days for Google to review the app and update the Play Store. So if you're affected by this, you can either use another device as a temporary work-around, or if you're comfortable side-loading apps you can install the new version of the app manually via this link: https://s3.amazonaws.com/data.warlight.net/static/Unity/Warzone.apk
The cause of this is a change made by the Lets Encrypt organization to their root certificate. You can read more about their change here: https://letsencrypt.org/docs/dst-root-ca-x3-expiration-september-2021/