What do you really mean with someone repeats registration by changing accounts? Please explain further with what you asked in the registration and how the users repeat the process. Also, in the title you've mentioned you want to ban, but in the content you just ask how to prevent it.
If what you want is to allow only one response per user, it is possible using google forms. The thing is every user should sign in their google account before the registration. The owner of the account should not worry as their email address won't be recorded and will be used only to restrict registering again with the same account. The cons is, it is still possible for a user to register again by using a different google account.
For more detailed explanation:
Restrict Google Forms to only Allow One Entry Per PersonPS. If you could explain more, we can think of another solution.
It means that there are people who create multiple accounts of Telegram and participate.
I see. We only accepted the login user for participation.
I hope this will lead to a solution.
thanks for your reply. I will send Merit.