...It was the flight environment that was the problem.
Just adding in some thing's for your sake
@Glenh & all others on this forum that will read this thread now & in the future...
The main culprit causing this incident wasn't as said, your drone... & the environment merely made the incident possible.
Even though it may sound harsh, the main cause was ignorance & that you didn't pay attention to info you got or didn't get from your screen.
Looking into the log you shared, clearly show that your screen device wasn't properly attached to your RC during the first half of the flight... nothing is recorded until approx. 56sec into the flight... so you didn't try to confirm anything there in order to secure your upcoming flight.
When the log starts to record we can read off that no HP have been recorded yet... which isn't strange as the Sat. count was low & the GPS level was only 2 (how much the flight controller trust the positional data... 5= best & HP is recorded when it reaches 4).
When the incident occurs the GPS level have just dropped further to 1 then shortly after to 0 ... & then the flight controller fall back to ATTI mode which still is possible to handle but you've lost all positional hold support, no auto braking when releasing the sticks & the drone freely drifts with whatever affecting it... so if not used to maneuvering in ATTI, not prepared for the switch & having the drone really close to obstacles... a disaster is very likely & not far away.
Below I've depicted the flight log in a chart including flight time, flight mode, Sat count, GPS level & calculated heading speed.
White background up to the 56sec mark = your screen device was most probably disconnected from your RC (or the app wasn't started)
Brown background = Ordinary GPS mode or Normal mode
Green background = ATTI mode
Green graph = Sat. count
Blue graph = GPS level
Purple graph = Calculated heading speed
The crash happens pretty much right after the GPS level have dropped from 2 down to 0... there we also see a rapid increased heading speed. (have placed the chart marker just there at 112sec... read off the graph values for that point in the chart legend in the bottom)
(Click on the chart to make it larger)