Time not updating when unlocking?

Hello,
I have seen old post but they were quite dated so I ask again (sorry for the repeating the subject).
i set a widget with the time, and the kustom app suggested me adding the location notification to update the widget. but sometimes when i unlock my phone it is not updated, sometime it is etc. I am missing a setting somewhere?
today there was like 30 min late diff

Go to KWGT’s app settings >> Advanced options. Enable “Update when Screen is off”. Also, make sure to remove KWGT from your device’s battery optimization.