I connected to a VPN and turned off location but telegram still show my country in registration form. How this is possible?
I used a VPN(Hola) to route through Switzerland and then I changed the location using Fake GPS Location - Hola to the same area the VPN was routed to (according to Telegram's check based on my IP). I also turned off my mobile data. I assume Telegram is keeping track of when the account was used where and then they just show the last location available in their database if the sudden change in location doesn't make sense.
Here you can see they got my location wrong:
Also when sending my location in a chat they show the fake location I set. Unfortunately, when searching for friends or groups nearby this is not the case.