Incorrect tag positions observed

I recently used the DWM development kit for my project and configured the anchors and tags as recommended in the guide.
However, I notice that the positions of the tags are constantly changing ( variation of upto 1.5 m from the actual position) even if the tags are stationary as they lie on the table.
The video of this issue can be accessed via the hyperlink below.
Can you kindly instruct as to what must be done to solve this anomaly? My project is getting severely impacted due to this.
Tag position

The basic system works so it must be something to do with how you have set up or are using the system. But you haven’t given any information at all about how you have it set up so it’s impossible to give advice on how to fix it.

Poor performance normally comes down to one or more of the following:
Poor setup - the anchors aren’t exactly where you’ve told the system they are or are mounted poorly in a way that distorts the antenna pattern. (e.g. stuck directly onto a metal surface)
Poor geometry - the anchors are in badly chosen locations relative to the tag location, doesn’t look like this is your issue.
Poor environment - lots of blockages with objects/people blocking the line of sight from tag to anchor.
Poor signal integrity - antenna gain or polarization issues or board / housing designs that weaken / distort the signal.

Antenna delay calibration can also cause errors but that will give a constant offset rather than a moving position.