Usually people use the same email address for all occasions - for personal correspondence, for solving some business issues, for registering in online stores, forums, social networks and for hundreds of other online resources. Over time, everyone has the same result: SPAM.
For clarity, I depicted this case in the picture above, when you use the same conditional address (email@example.com). Yes, you can find out from which server spam comes to you by looking at the letter code and you can even try to block the source - but you will never know WHERE the spammer took your email address because it is everywhere - it is used at every point of the internet and this is very easy prey for all sorts of scammers.
It would seem this situation is hopeless, but there is a way when everything will become transparent and understandable for you. Here's a look at this second picture below.
I implemented this project in 2013 and it is built on the principle of indicator email addresses. This requires a lot of unique email addresses (in my case there are from 50 to 100) and for this you need the services of a hosting company which will be able to provide you with an unlimited number of email addresses on your domain with the ability to set up a redirect between them. All these addresses must be unique for each online service and their names must be known only to you. For convenience, your email client reads only one main email address to which the redirect from all the others is configured. You will forget about spam.
The sudden appearance of spam will indicate to you a "depressurization" of the database of one of the resources that you are using and one of your indicator e-mail addresses will point you to which database fell into the unauthorized hands (the picture shows a case of personal data leakage from your bank). After fixing this event, you can replace this email address with a new one and stop spam until next time. This system works effectively since 2013.