Locations with the following IDs have invalid coordinates:
8591907, 8594070, 8588540, 8580153, 8587340, 8594076, 8506723, 8573960, 8583057, 8589565, 8583397, 8573977, 8589556, 8573969, 8579892, 8500000
Make sure you named the columns "lat" and "lon" and did not confuse latitudes and longitudes. The coordinates must be in decimal form. If your coordinates are in degrees-minutes-seconds (DSM format) you can convert them with
this tool for example.