Google Forms Help

Hi, I have a google form set up were I have employees sending in requests for days they want to book off. The problem is I only want one employee off a day, is this possible with google forms? So if an employee was to send in a date that was already in the spreadsheet it wouldn’t allow them to submit the form. Hopefully someone can help. Thank you Phillip

There has to be a way to do this… here are a couple of references that may help:

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