There are many fake airdrops that are used to collect the details of airdrop participants so they csn spam them on telegram and use their details(email addresses). I personally have been a victim of this.

 I suggest before joining an airdrop you verify the authenticity of thr drop so you do not all a victim to identity theft or even worse, have your accounts (email especially) hacked. This is something those that use only one password across various platforms are susceptible to.