I was doing my firts 70 min FTP test and my iphone froze with 2 mins to go.
I was using a Wahoo kicr with a Iphone 7.
I had to restart my iphone and lost all the data.
Any ideas?
If the entire phone froze, not just Zwift, it might indicate that the phone was over stressed. Which could have lead to a hardware error, such as overheating. If this was the case, you could try limiting the number of background apps, by force closing all other apps before using Zwift.
If the activity shows up on your Zwift Dashboard, https://my.zwift.com/ , you might be able to recover the part of the ride via fit file (as long as the crash didn’t corrupt it).