There are a couple of reasons as to why children can have negative tokens
Let's assume that your child is not allowed to have token debt (from settings)
If it is a small number like -1 or -2 this is ok because because when time runs out you can take up to a minute to block the devices , which will use some tokens.
If the negative number of tokens is very large like -30 or -50 or more, this tells us that the device is still being used when it should not be allowed to be used AND the mode being used AND has a disallowed token time multiplier enabled.
And there are two scenarios for this.
Scenario 1
If you have apps set to be always allowed to be used and the mode does not have zero set as a disallowed time multiplier then it will still continue to consume time (and go into negative)
If you do want them to be able to use these disallowed apps without any charge against their free time or token time then change the mode and set it to be Free time when disallowed
* another option is to create a separate mode which is free time and set the times of the day. This mode can be used and set the apps that are allowed to be used for that mode.
Scenario 2
App blocking is not enabled or not working correctly, so Sessions are running and using time
The most obvious thing to look at in case apps are not been blocked specifically on iOS devices is
- Apple ScreenTime is still enabled - Please disable it
- That Apple Screen Time may have some apps that are always allowed to be used, even if you have turned off!
(this is an apple bug) - Please remove them- Apple screen time these settings can sometimes still be working in the background even if disabled ... so you need to enable Apple Screen Time then remove all of the screen time options like: always allowed apps, down time, and app limits. Then turn OFF apple screen time again.