Take a look at this post - Missing some plots in chia gui - #4 by seymour.krelborn
It describes (at the bottom) how to locate your chia.exe folder. One thing to add is that it may return two results, one starting with upper- and one with lower-case letters. Go to that with lower case letters.
You can also follow @ChiaJoe instructions above, although instead of the initial c:\users\xxx I would use %userprofile% followed by the rest of what he has there.
Once there, run the following commands:
chia plots check -n 5 -g f:\new_plots\*
and
chia plots check -n 5 -g g:\old_plots\*
We would like to know whether plots in the old_plots folder have same responses as the new ones, or rather chia will tell you that those are not your plots.
Basically, try to run it, ask for help if you get stuck, and let us know what you get. Someone will always help you to get through it.