Two ComboBoxes that filters out an item in one ComboBox if selected in the other Combobox

Hi. I would like to create 2 ComboBoxes (ActiveX Control). Both will have the same list. If an item is selected in ComboBox1, I would like that item to be filtered out or removed from the selection in ComboBox 2 and vice versa.

I want to have the following list in ComboBoxes:

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I already tried using Dynamic data validation but it will still let you select same 2 items in 2 drop down list.

Hope someone could help me. I tried every solution I found on net but non of them worked.

create a function that adds the items to the combobox based on the combo box before it. send the previous combo box and the new combobox to the function. create a do loop that loops to the end of the list of the first combo box and use the add function to copy the list of the first combo box to the new combo box with the condition that the text in first combo box does not equal the list value of the first combo box that the loop is currently on. the only issue with this you can only add one at a time. my solution is to grey out the first combo box when they make a selection. I then have a go back button to undo the selection and modify the first combo box. not sure if this is the solution you are looking for but I hope it helps.