When uncheck checkbox, every other checkbox is greyed out

I made a website for a client, i’m using the Woof filtering plugin! It works great except there is one issue. Sometimes, when you check a checkbox, the filter is loading items. But if you uncheck that same checkbox, every other option is greyed out.. so you can’t select any other option and have to refresh the page. That is not correct, can you help me please?

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