Me and my wife both use zwift. Whenever I use it, I fire up the tv and apple tv box, log in, make sure my smart trainer (kickr core), cadence sensor (kickr sensor) are all linked and away I go, no issues. Zwift companion works fine, allowing me to use all functions and give ‘Ride On’ like they are going out of fashion.
Whenever my wife logs on, she does the same, but when actually riding her Zwift companion either doesn’t link, or if it does, her phone then drops off the wifi and goes into 4G mode. Therefore disconnecting from zwift and being useless.
I cant for the life of me work out what I have done differently on my phone compared to hers. We were both on iPhone SE’s, although she is now on a 6s and the issue still persists.
If not for the fact that she has had the issue w/ two different phones, I’d tend to think that there’s an issue with her phone’s Wifi. I had an iphone with wifi that completely stopped working after I dropped it.
Can she use your companion app (i.e. your phone) w/ her Zwift account w/o problems?
Could it be that the wifi signal where your trainers are setup is occasionally on the weak/marginal side and that her phone reverts to 4G sooner/more frequently because it’s just not as good as picking up the signal as your phone? Or that you’re busy doing other things sucking up bandwidth while she’s on the trainer?
Turn off “Wifi Assist” in Settings. When you have a situation where your wifi is perhaps not completely reliable, iOS will send some packets over the mobile network to see if that results in a better round trip. This seems to confuse Zwift Companion and stops it pairing, or makes it drop the currently paired connection.
I used to have no end of problems with ZC in my garage set up, but since turning off Wifi Assist, I’ve had zero issues.
The alternative is to put the phone into Airplane mode, but with Wifi active, each time, but you have to remember to do this, and remember to turn back to normal after your ride.