No App Connection to Race Timer when mobile data is turned on

[ps915]

Hi just faced problems to connect to the Race Tracker via Wifi.

I discovered, i need to turn of the mobile Data. Then it works perfectly.

Phone: OnePlus 5T
Android: 8.0.0
OxygenOS: 5.0.3

Anyone having the same issue?

[AABatteries]

Hotspot provided by the Wifi module obviously doesn't provide internet access - modern versions of Android will detect that and will still use mobile data despite being connected to the hotspot. Turning off the data is one workaround, the other one should be a notification in the statusbar that pops up after connecting to such a network - "Access point has no internet. Touch to configure" (or something similar sounding)
After clicking the notification there should be an option to stay connected to the AP. That should solve the issue as well