Attached is a photo saying I was kicked and unable to connect me to the server. Every time I type "/join *my server name*", it shows "joining world" but it just brings me back to the lobby again. A few hours ago, it was working just fine until this error showed up saying Connection Lost / Disconnected. I was the only one in that server at that time so I asked my friend if it's happening to him also, him trying to join the server also showed Connection Lost / Disconnected.
Can someone kindly tell me what's happening and assist me on how I can fix it?
***UPDATE***
I restarted Minecraft and now this error shows up: full server capacity and unable to start your server.