Formatting issue with thousands delimiters

Hello all,

This is my first time posting so please let me know if I can improve in anyway. I was given a data workbook with the data formatted in a very weird way. Whenever I format the cells I need to work with to "numbers" some cells don't always get formatted the right way. In order for excel to recognize the number and be able to use it in formulas I need to add a 0 value to it. My issue is there are about 3500 rows and in order to add 0's would be a little bit time consuming.

In the attachments I have uploaded one PDF with before and after screenshots and the original spreadsheet.

Thank you