Sorry that is a problem in the WIndows desktop program. You need to save each return with a unique name or as you found out if you have the same first name it can overwrite the first person's return. Maybe you can find the special backup file from earlier. There might be a copy of your file saved, it starts with a Tilde ~ sign. Maybe you can find that one. The tax files should be in Documents then in a Turbo Tax folder.
Try going up to FILE - OPEN and see if you have any files starting with a Tilde ~ sign. Maybe one of them will be your return.
