Hi Novneet,
We have analyzed your query. We suspect that in you might have specified region of annotation property to AnnotationRegion.plotArea. If you have specified this, then the annotation will be visible only inside the plot area and if the annotation goes out of the plot area, then it will be hidden. To make this visible, kindly assign AnnotationRegion.chart to region property, so that annotation will be visible properly.
We have also ensured with visibleMinimum and visibleMaximum properties and the annotation is working fine.
We have attached a sample for your reference which can be found below.
If you face still any concerns, kindly modify the above sample to replicate the reported scenario and also confirm whether you are updating the content of the annotation for example text of annotation for every 15seconds? Revert us with the above information, this will be helpful in further analysis and provide you the solution sooner.
Thanks,
Dharani.