Gmod mulitplayer issues

When I try to load up TTT servers, either they wont load (just a white screen), or it gets stuck at connecting to server. Sometimes I can get it to work and Im able to connect. Everything is allowed through the firewall (Gmod, Steam, hl2). I tried turning off the firewall, reinstalling Gmod, restarting my computer. Nothing is working. Any ideas?

How are you starting the server?
And also how are you trying to connect to the server?
Are you sure that when you try to connect to your server it has initialized?

Now when you say you’re loading up these servers are they ones that you yourself are hosting, or are they found through the server browser?