So the picture below is the issue. I've looked across the internet and found no answers, no one bringing to light the fix for this problem. I made and bought a brand new server, installed everything properly, I know because it was a new automatic feature of my host provider. I'm running Pixelmon Reforged 7.1.1 and Minecraft 1.12.2 on the server, and on my client side. I cannot join my server because of above issue, my friend cannot join my server because of above issue, I've encountered the above issue when trying to join one other Pixelmon server running the same specifications, and was able to enter another with seemingly no issue. I cannot fathom why this is, there is no other mods, nor plugins in my server other than the base Pixelmon mod. There is no log in my servers console when either my friend or I attempt to join it. This apparently has been an issue unaddressed for a significant duration of time and I would like to find a clear answer that all others who search up this problem can find here on this page. I will provide you whatever necessary information you may need to further progress towards this solution as I'm incredibly irritated that I cannot join the server of which I've now paid my hard earned funds on. As a note, clicking yes does nothing but return you to the main menu, and clicking no results in the same. Please help me, as well as all the others having this strange and irritating issue find the answer!