​@vitrics this is not possible, and I'm pretty sure there are restrictions around this to avoid spamming in Telegram.

I think your only option is to get users to opt-in to your Telegram bot.

Thank you so much ​@Gustavo Boregio I have turned on the opt-in algorithm. At the moment, I am working on two accounts where one account I can directly click to my opted-in user telegram and the other cannot. I will share sample below of what I meant. 

The first image has telegram user name so I can chat with my user on telegram whereas the second does not have. Is there an option to turn it on like the first image.

​@vitrics if the person deletes the conversation (2nd image) you won’t be able to contact them.

but the first image also got person deleted the convo

​@vitrics got it!

I'm not sure in this case.

I'd have to do some testing to get to the bottom of it.

My guess is either there different personal privacy settings in these accounts, or the 2nd account had the Telegram account deleted and therefore disappeared.

You can also always check with support to see if they have better insight into this scenario.