Apologies in advance if you're not a techie type person! There have been several posts on this before - using the Search box above gives:
https://blipfoto.zendesk.com/hc/en-gb/search?utf8=%E2%9C%93&query=lat_invalid&commit=Search
Think it's some sort of error generated when interpreting the GPS information that's contained within the EXIF data of your photo - lat as in latitude. If you're using a camera that doesn't have GPS, you shouldn't have this problem. If your camera does have GPS, you could try turning it off. Suspect all phones automatically add GPS type info.
Alternatively, and for shots already taken, if you want to keep GPS information with the photos (to remind you of the precise location), you may be able to remove it from the files uploaded to Blipfoto, via your editing software, and/or the EXIF data. The EXIF gives all sorts of technical info. about the camera/lens used, along with the settings, and date + time... if it's been set correctly! Removing that may get around the problem... but your camera and settings information won't be available to be viewed, and you'll have to pick the correct date to load the photo against.
Hope that means something to you, and helps a wee bit!
Best wishes.