How do I clean up a corrupted Numbers spreadsheet with duplicate rows/columns?

I'm creating a Numbers spreadsheet to gather information to add Men's Groups to a new Directory that I'm building.

It has many rows/columns that I will eventually add to my directory. I have just opened it, and it appears to be corrupted, with many rows/columns appearing as duplicates. Visually, it's very hard to read and see what is there.

I have saved the spreadsheet as a .csv file; all of the data seems to be there. How do I clean up the file, or do I just use the *.csv file to recreate a new Numbers Spreadsheet?

I can upload the file to be seen?

[Re-Titled by Moderator]

Original Title: Numbers file formatting