Hizpo - S8-8G Octa Core 7862

If the application creating the link with your Android phone (normally, this is the zlink app) is stuck / crashed, the only way to fix the situation might be to perform a full reboot of the Android system of the S8-8G. This is not easy though; there is no direct access in the interface for this. You will need to go to Settings -> Device -> Factory -> enter 8888 as a code -> go to Phone Link App (item 42) and change the value. This will ask you for a mandatory reboot, which you can allow.
Note that there is one other application to manage the phone link, but I could not get it to work (it looks intended specifically for the Chinese market).
The sleep time setting is an important one (in Settings -> Device -> General -> Sleep time). It actually is very counter intuitive because "sleeping" actually means not performing a full reboot if the car engine is powered off then powered on. For instance, if you select "Sleep for one day", the system will perform a full Android reboot if the car has been turned off (unused) for more than one day.
Usually, you never want a reboot (unless there are issues and the system is stuck), as this is a long process. Thus you want to sleep for as long as possible. The maximum allowed value is 7 days, and should be selected. Don't select "Do not sleep" as it implies a full system reboot at every start of the car engine.

Android Car Radio Multimedia Systems