Using addmarker does not display

I’m working with Vue. I want to try addmarker. The screenshot shows the code I wrote. You can get relevant information during debugging. But there is no display on my page, and there are no errors. Other functions are normal.
image image

The native code of the pro version I use.

You need to make sure that the current date is visible in the timeline. If it is outside the displayed date range, there should be no marker to display.
Here is the Vue demo where the marker is displayed correctly:

If that doesn’t help you, please, send me a ready demo with all the necessary files so that I can reproduce the issue locally.