Hi Guðmundur,
Greetings from Syncfusion support.
We have checked your requirement and unfortunately, we could not reproduce the reported issue at our end. So, we have prepared the sample based on the provided code example and attached it below.
Still, the issue persists, please revert us with below details that will help us to check and proceed further.
1. Issue reproducing sample
2. Code block of the fired event for DatePicker component
3. Any other configuration details enabled in your application
4. Modify the provided sample with the reported issue
Regards,
Sureshkumar P