when I use 4 anchors and one tag, my tag receives with 4 anchors range data, and sometimes it will jump to a large range number, which is not normal since I did not move the tag at all. Has anyone had the same issue and has the solution?
Hope to solve the problem soon 
Your own code or PANS?
Range to all anchors jumps or just one?
The short version is your system needs to cope with occasional bad values.
You can get incorrect values for all sorts of reasons, some you can minimise, some are outside your control. Massive jumps to unfeasible ranges are easy to detect and ignore, smaller jumps to incorrect but plausible ranges are harder to cope with.
As a most basic solution you can measure 5 times and take the median, that will normally work as a very quick and simple way to ignore occasional outliers.