Error connection using aiohttp on Aiogram

With any proxy, even if it is 100% working, it gives a connection error. What am I doing? I search for sites with a free proxy, copy the proxy, insert the checker into the proxy, then paste it into my code. I did everything according to the documentation Aiogram, there can be no mistakes. And even if it's socks5, I additionally insert it into the Telegram proxy to make 100% sure that it's working. And even in this case, it gives a connection error. What should the gentlemen do? Maybe it's a feature of the free account that I can't deploy my telegram bot, even using a proxy? An excerpt from the documentation I followed: *link*

Free accounts have restricted Internet access, which means that they can only access the external Internet through a proxy that we provide -- they won't work with third-party proxeis.