Battery Life Not lasting more than 8hrs

Hi, 

We just bought a Garmin Bounce for our daughter. It is on charge during the night and she wears it to school during the day. The battery life is not lasting the day and turning off before school finishes which is not meeting the intention of her messaging us when leaving school and arriving home. Screen display is low, vibration alert on low and screen time is set to short but still having issues. 

I can't help but think there is a problem with the battery even though it's new?