Have you checked out the app General Caster? Its available for free on the Monday.com Apps Marketplace. It replaces the need to use the formula column, which could “clear a date” in this scenario. But the formula column often isn’t supported alongside other Monday features yet.
General Caster is here. Get rid of formula columns!
So you would instead have General Caster setting your initial due date, and then you should be able to set up a simple “SWITCH” or “IF” formula that sets the date to “”(empty) based on a status change.
Without knowing more about your setup, I can’t give specifics, but if you want to share a screenshot or more details, I can help you set this up with General Caster.