Automatically disconnects from a public wi-fi.

[Android Central Question]

Galaxy S8...While at a hotel I was connecting to the wi-fi and a small box popped up (it happened really fast so I don't know exactly what it said) and said basically that I was attempting to connect to an open network and that that it may be unsafe. It asked do I want to connect or disconnect and it also said it would remember my choice for the future. I accidentally selected disconnect! Now, every time I go for a conference I try to connect, which it does for a split second, then automatically disconnects. I've tried to "forget" the network then reconnect, still disconnects me. I also reset the network settings (which meant I had to re-enter my home network password) but once again, as soon as it connects to the hotel it automatically disconnects. How can I undo what I did?