Problem Ive been having a horrible time trying to get this server to work, could someone please help me

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I'm not an expert by far but the initial thing that jumps out at me is that you need to be running a later version of Forge.

need [14.23.5.2838,): have 14.23.5.2836

Try updating your Forge 1.12.2 version to 14.23.5.2838 or later and see if that helps.