In some geographic areas the quality of satellite images can be low and it’s not possible to see buildings with enough details to accurately align floor plan images. Please, try to change the map provider from the top right of the floor plan alignment view to find the best map view with enough details. The current options are: Mapbox Street/Satellite, and HERE Street/Satellite.
You can also use geo-coordinates to place your floorplan image – you can add lock points to your floorplan image and add the corresponding geo-coordinates from the “Exact coordinates” menu. See a video tutorial here: https://youtu.be/YD9afmVwTe8?t=71