How do I determine whether a specific item has appeared in a list multiple times?

i'm a beginner in mit app inventor and am making an app that prompts the user to type in their name and their email-- im trying to make it so that every time the user types in their name then it will save it to a list and once they typed it in more than three times it sends an email to them. the problem is that i cant figure out how to determine how many times their name has appeared in the list, and how to differentiate it from other people that may put in their name. i tried using a variable but then it saves everyone in the variablel and not just one person. im not using tinydb or anything. if anyone could help i would really appreciate it.

Are you saving anything more than the count of how many times they entered their name, like date/time info?

If not, then you could pull in a TinyDB instance with a NameSpace LoginCount using names as tags and login counts as values (0 if not found). Call it tdbLoginCount to separate it from any other TinyDBs you might keep, like tdbEmailAddress.