If the flow starts with any Ringer Mode trigger in Android 10 the Automagic stops execution and switchs off that flow with message "Interrupting and disabling flow".
In the log file I have next lines
Even if set emergency stop limit over 60 actions (e.g. 600 or more), this stop occurs anyway.30.11.2019 15:10:33.021 [Manual ringer mode] Emergency stop count reached, disabling flow and current flow execution
30.11.2019 15:10:33.055 [Manual ringer mode] Emergency stop reached, stopping flow execution
Usualy issue reproduces when the ringer mode is changed manually from notiofication area.
Flow execution policy in this case is set to "Wait until the current executing instance has finished".
A little bit helps policy "Skip execution when an instance is already executing", but anyway this issue occurs.
If it may help I got this issue on Xiami 9T Pro with Android 10.