Hi Stephane,
Greetings from Syncfusion, we have tried to replicate the reported issue at our end by creating a simple sample, we are afraid that we are not able to reproduce the issue at our end. We have tested the below mentioned scenarios and used ObservableCollectiont to bind data.
1. Tested by removing data one by one and added new data dynamically using button click.
2. Tested by clear the data collection and adding new data dynamically.
3. Tested without setting any minimum and maximum value for the DateTimeAxis.
Please find the tested sample below.
Since we are not aware of your exact application scenario, we were not able to reproduce this issue at our end, so can you please revert us by modifying the sample based on your application along with replication procedure. This will be helpful for us to investigate further and provide you a better solution at the earliest. And update the SfChart to latest version and check once whether the issue still reproduced.
Regards,
Bharathiraja