(URGENT) How to set error bars for data points seperately?

So I have a line graph and two point connecting together at first and then I click no line, after clicking no line there is literally no line connecting those two points. Now what I need to do next is to set error bars to those now "separated" data points individually. Because I have different error bar values for each data point, but every time when I want to select only one point It automatically select the two points. How can I select the data point one at a time?

HELP ME PLEASE!