Add IP limit feature

Hi team, I noticed that, there should be more IP restriction feature for account registration I am facing the situation, one person but they can sign up for multiple accounts by taking advantage of the free plan. This leads to a lot of junk accounts, after they run out of free words and they quit that account and create a new one. Please add IP restriction feature. That is, each IP can only register from 1 or 2 accounts. Thanks