Countm Distinct formula for multiple dropdown column


When I use the countm(distinct()) formula, I get an answer of 4 instead of 3. This is a drop-down list with the option of having multiple values per cell. There are no extra spaces in my cells. The formula seems to know that there are 3 different options in the blue highlighted cell but is unable to see that the "K-S-212" in each cell is the same. How can I go about fixing this?

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