How do I fix an issue with a limited connection on public wi-fi? It only happens at a certain location.

There is a coffee shop I go to where I cannot get a normal connection on their wi-fi network . I use public wi-fi frequently and it typically works fine, but at this location I only get a limited connection. I've used it there previously and they have it password protected. It worked for me the first time I went there but since then I can't get it to work. I tried all the usual fixes - forget this network, turn wi-fi on and off on my laptop, re-boot, any combination of those three, but I can no longer get connected no matter what I do. I know I'm using the correct password, it seems to log me in, but I cannot get more than a useless limited connection. Is there something I can do to fix this? Like I said, I've used public wi-fi successfully at many locations and never had this issue. I've used it at some locations where they have it password protected and then they change the password, but all I have to do is choose the 'forget this network' option and then it works fine. Nothing works for connecting at this one location, and the people who work just say things like 'there's too many people on it'. They're not exactly network specialists. any help is greatly appreciated!