grouping data in excel

I’ve got a huge excel report full of data. 2 columns of interest that I need to filter, are invoice_num and amount_paid. Each invoice_num has a number of rows of data associated with it, but the amount_paid is then duplicated each time  dependant on the amount of lines of data associated with the invoice_num. I need a way to filter the data to only show the top line of data per “invoice_num” to get the figures down. Some example data below, you will see for example 4 rows of data for the invoice_num 67890. I need a way to filter that down to just the top row! There is also many other columns in between these 2 but they are the main ones.

12345          1612.46
67890          1929.39
67890          1929.39
67890          1929.39
67890          1929.39
99999            23.12