How to add constraint in table list

Dear colleagues!
I would like to request your support
In fact, I’d like to add a constraint so that if the person selects the month of January in the first line, he can’t choose another month in the following line he need to choose only January in the second line…
Here’s the example in my photo

@dofrancis3, this support article Adding Calculations and Constraints in a Matrix Question should help you solve your issue.