I restored - now I have two companies- what should I do?

Early in June I made a stuff up, and had to restore a back up copy.  During the process of the restoring, it sat at a prompt - like it was asking me to name the file. It wouldn't progress unless I put something in - it had a .Q something behind it. So I did. Worrying that it might not work, I called the file Restored Data and a date. The restoring worked and I have continued to work through, balance - everything is great. BUT, now I have just gone to upgrade to 2018, it took me to a page that shows there are 2 companies/names in my system and has asked me to pick. Normal everyday log in never asks me to pick, it just goes straight in. The original named one (which has our company name only, and the company Restored Data....   As the restored data is the one that is current (and I know this as I back up everyday and it still says Restored Data) I've upgraded it and everything is fine. 

So, my questions are:

1. Do I need to delete the old company (which has old data before the restoring incident) - and if so, how do I do this - and how do I even get to that screen again where I can select a company file, as I go straight to the normal desktop screen.
2. If I do, should I then rename the remaining company that has now been called Restored Data
3. Should I just leave the original company in there and just upgrade it to 2018 as well, and look at deleting it down the track...  I won't be using this again as now the Restored Data name file is the current one.

Sorry, I know there is only one company, but there are 2 files and I'm getting myself confused every time I think about it.

Any advice would be appreciated.  Many thanks.