Scammers in Telegram, well, there are scammers without Telegram, just why position a beautiful creation like Telegram with scammers, Telegram is a multi-functional tool with the ability to create a bot and a lot of other functionality, but as the question comes to do something useful through Telegram, many say telegram and there are scammers.
Scammers always use anything to cheat, right? not just telegrams, even many who use social media accounts, email, phishing, etc. So, this is not the fault of Telegram.
I often get PMs from individuals who invite investment, ask for funds, and other modes, I automatically report the account. If the fraudster's account is reported a lot there will be a red tag and a warning, so take advantage of the report feature to help so no one is fooled.