Unable to filter data using multiselect

So far I’ve retrieved my data frame without issues and would like to incorporate search and filter functionality to my app. I have no problem with searching (select boxes and slider), but filtering is not doing what I want it to.

I’m trying to filter my data using the values of two multi-select boxes and one multi-slider input. However, whenever I try to incorporate either of the multi-select boxes in my filtering process, it crashes the app. Any help in how to fix this would be great! Thanks!

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