I had the same issue (on Windows) for a very long time and I was so used to it I could drag the pictures to a place so they would appear in their almost exact location (centimeters away). In the past few months noticed that it finally worked fine, without doing anything except keeping everything updated. Now on LrC 10.3, it's still flawless. So, really not sure what's the cause, maybe you'll find a working solution in the linked thread.
Hope that helps,
Michael Niessen - Photographer, photo-editor, educator
To build on Michael's reply: That bug report describes a workaround that works for most people. Instead of dragging the photos to the map, select them in the filmstrip, right-click the desired location in the map and do Add GPS Coordinates.
The occurrence of the bug seems to depend (at least in part) on the current settings of Windows display scaling and LR's Preferences > Interface > Font Size.
This is an old bug. Please add your constructive opinion to the bug report and be sure to click Like and Follow at the bottom of the first post. That will make it a little more likely Adobe will prioritize the fix, and you'll be notified when the bug's status changes. Product developers rarely participate in this forum and won't see your feedback.