Wyze cam notifications occur after a 12 second event has been uploaded to the cloud which is in contrast to notification upon initiation of an event. This is by design. That 12 seconds may become minutes depending on numerous factors such as throughput speed, network latency, cloud server status, etc. If you haven’t already done so, please vote on this Wishlist item to effect possible future change:
Immediate notification of event
I had the same problem until I changed system settings on my Samsung, Lenovo and HTC devices. In the name of saving battery power, some devices running later versions of Android put “unused” apps to sleep making them unable to receive and display/sound notifications. Users need to configure this function in system settings to allow the Wyze app to run in the background (i.e., prevent Android from putting the Wyze app to sleep). These settings are ususally under something along the lines of “App power management” in system settings > battery and/or Apps > Wyze > Battery > Allow background activity and/or Battery optimization.