If I sell my account, they will use my name, contact my friends and other members, and ask for money. If I have a good reputation on the forum or any other online platform, they will go there and ask for money or scam people in different ways. But the scammers actually do not want to buy any username. They just created a new telegram account and used a similar username, so people believe they are the original one.
It is true and as I wrote, there are only two possible ways how it ends.
- Contacting you to purchase your reputable account, and use it for scam around like with your family members, friends, who are in your contact list inside and outside the forum.
- Scamming you directly, if your account is useless and they don't need to buy it.
Hence, when you receive such contacts, you must be clear with yourself, how valuable your account is. If it is useless, ignore the offer that is intentionally aiming at you for scamming you.

There is a way to prohibit them to contact your friends and contacts upon selling your username to them. First convert your username in to a group name and your username should be the url by choosing it to be a public group.
This means you will create another username of your own and you once again will decide for the url of it. What you will be selling to a buyer is just the url of the username. Tried a transaction before but didn't push through because someone said its best to use the fragment.com