Hi Laurence,
Greetings from Syncfusion support.
Based on the provided code and screenshot, we suspect that you have assigned the value to the DatePicker component which is minimal of min date of it. So, the provided value set to the component with strict mode validation. So, the placeholder is not shown and value is displayed in the component. While defined the component without value property, then placeholder is shown correctly in the component.
For your convenience, we have prepared the sample and attached it below.
Also, please share the below details which is help us to check and proceed further at our end.
1. Have you rendered the DatePicker component inside the Grid component?
2. Share the code for assigned date time value for value property.
3. Simple sample or modify the attached sample with reported issue.
Regards,
Berly B.C