I fixed my problem by accident.
I think the no gps fix started around ios10 and lasted till now. But when i was fiddling with my mail settings, noticing the odd | new data: ‘push’ | option at the bottom of the accounts and password page in ‘settings’. . Could that be the culprit? I flipped the switch and instantly gps had a location fix.
So: to turn on gps location fix just flip ‘push’-button to ‘on’ under settings - accounts and passwords’ - new data : push>