Thanks Jhieminga, good suggestion. I plugged in a USB WiFi dongle and enabled it in the network manager, disabling the built in Wifi at the same time. After not very long the network connection locked out pointing to an issue with the driver software in the OS. Some Googling found other folk with a similar issue a few versions of Mint ago with the suggestion that the network manager and power manager (it is a laptop) don't always work together as desired. One of the suggested fixes is to open a terminal window and to type in a few lines, given, to change the settings but when I did it asked for a password for github that I don't know. Still checking down that route.
Rans6........