If Plato seemingly goes in the wrong direction when given a mission, it is possible that Plato lost its localization. 

First check where it is situated on the map, on the remote tablet. 

You can go to Map > Edit Map > Annotate your map.

This will give you a view of your map, and where the robot is on this map (the blue cursor). 

You can do a first check of where the robot is situated on the map and assess whether it indeed lost its localization or not. 

If it is indeed lost, you will need to relocalize Plato. Please check this article to see how to do it.