How did You do the copy?
There are several ways and restoring depends how it was done.
easiest way - would be if You have Just copied the company in the Company List.
Then it could be that You can delete the Original company, and do a Copy of the Copy again and give the Original name again. That way all web services or integrations will work again (if there were any). Might want to make a DB copy if possible before doing this :)
If You did an Export to a data file, then You can do an Import of data file
Other way would be an SQL or Azure side copy of whole DB.
