U-blox GPS timestamp incorrect in data logs

I’m having an issue with the GPS timestamps in the datalogs. The timestamp (in milliseconds) should represent UTC time, but the log is showing a time in msec around Jan 1970. I have checked all my logs on 3 different platforms (1 multirotor with APM, 1 multirotor with Pixhawk and a plane with Pixhawk) that have the same problem. I am using different u-blox GPS units on each platform.
The strange thing is that when I connect to the u-blox configuration software (U-Center), it shows the correct UTC time.
Anyone have any idea what is going on. I live in South Africa, so maybe there is an issue with the sat feed, but I always get strong signal with at least 8-9 sats.
Very annoying because I can’t georeference my images.

I’ve attached a screenshot and example datalog file

UTC and GPS time are not the same, there is around 17 seconds difference at the moment.

Thanks, yes I do know that. The issue is that the timestamp in my datalog is showing a date of Jan 1970. I’m talking about the TimeMS column in the GPS field of the datalog that shows in milliseconds. This is the time that is used for georeferencing correct?