My Virgin Mobile LG Stylo 2 just updated to Android 7.0. Norton Mobile Security reports "Unsecure connections" even though I am on my secure home network. I've only had phone a 4 days but do not believe it happened before the upgrade.
The closed lock symbol should be for a secured network.
The others are just listed to remind you that they are unsecured networks if you decide to connect to one of them. Just be sure you do not do any sensitive transactions while on one of those networks.
HOWEVER. This has NOT happened the last 3 days. Now only Denny’s, Walmart,etc. show up. So I am not certain if the issue has vanished or not!
Mine shoes my home network with the closed lock symbol on it.
If you tap on unsecured networks on the main screen of NMS, what networks are shown? On my phone, the unsecured networks were for retailers that offer free wifi, like Walmart.