First thing, the

The "+3" values are treated as explicitly as text! Not Numbers
If you use F2 to edit the cell you will see the leading ' that forces it to be text. remove the apostrophe AND the +
Select the whole column and define it as a number (0 decimal).
What is HDCP (just curious)?
Why are some HDCP +3 others values like 12 / 15?
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Your dates are also text, rather than date format, but that seems to be working (surprised me!).
Are the dates sorted in the order you want?
Normally, I would convert the text dates into excel date formats, but if it is working the way you want, I won't mess with it.
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Is this what closer to what you are looking for?

I've copied your sheet into my example workbook, look for it there:
You can look at this example in my online example file
https://1drv.ms/x/s!Am8lVyUzjKfpowARghSdfg1koqJf?e=H0lKb5
Link to this workbook. Look for the Tab with your ID on it
Note: In my notes for creating test data I suggested using small, simple data sets to make it easier to verify the results. For example, I would use fewer dates. Put more people on the same dates. Just so you don't have to scroll off screen to see the data
on the far right end ...