Hi anu_1555,
This one might be a bit tough. In general, data labels' placement can be adjusted with x and y options, but there is no option that could simply increase distance between a data label and a point.
Demo: https://jsfiddle.net/BlackLabel/vyxa0knj/
As you can see in the demo, I have slighly changed y value, and in this case data labels look good, but sometimes they are placed below point, for example when point is located close to the top edge. In that case label would most likely overlap with the point.
You could try to implement your custom solution, for example, iterate over points and compare point position with data label position and based on that adjust the placement. Unfortunately something like that can be complicated and frankly speaking goes beyond support scope.
Let me know if you have any further questions!
Regards!