
\documentclass[journal]{IEEEtran}
\IEEEoverridecommandlockouts
\usepackage{url}
\usepackage{footnote}
\usepackage{tablefootnote}
\usepackage{amssymb}
\usepackage[fleqn]{amsmath}
\usepackage{bm}
\usepackage{placeins}
\usepackage{textcomp}
\usepackage{amsmath,amssymb,amsfonts}
\usepackage{breqn}
\usepackage{diagbox}
\usepackage{csquotes}
\usepackage{mathtools}
\usepackage{algorithmic}
\usepackage{graphicx}
\usepackage{subfig}
\usepackage[linesnumbered,ruled,vlined]{algorithm2e}
\usepackage{float,caption}
\renewcommand{\arraystretch}{1}
\setlength{\tabcolsep}{4pt}
\usepackage{textcomp}
\usepackage{xcolor}
\usepackage{ mathrsfs }
\def\BibTeX{{\rm B\kern-.05em{\sc i\kern-.025em b}\kern-.08em
T\kern-.1667em\lower.7ex\hbox{E}\kern-.125emX}}
\providecommand{\nr}[1]{\textcolor{red}{[{\bf #1}]}}
\newcommand{\subparagraph}{}
\usepackage[compact]{titlesec}
\usepackage{cuted}
\usepackage{makecell}
\renewcommand\theadalign{bc}
\renewcommand\theadfont{\bfseries}
\renewcommand\theadgape{\Gape[4pt]}
\renewcommand\cellgape{\Gape[4pt]}
\usepackage{hyperref}
Antwort1
Zu viele Kommentare und nur Vermutungen ... aber vielleicht bekommen Sie eine Idee, was Sie tun können (zumindest bei der Vorbereitung Ihres MWE, das wir brauchen, und beim Bereinigen Ihrer Präambel):
\documentclass[journal]{IEEEtran}
\IEEEoverridecommandlockouts
%\usepackage{url} loaded by hyperref
\usepackage{footnote}
\usepackage{tablefootnote}
%%%% collected to math related packages, which one you really need?
%\usepackage{amssymb}
%\usepackage[fleqn]{amsmath}
%\usepackage{bm}
%\usepackage{amsmath,amssymb,amsfonts}
%\usepackage{breqn}
\usepackage{mathtools}% also load amsmath
%\usepackage{ mathrsfs }
\usepackage{placeins}
\usepackage{textcomp}
\usepackage{diagbox}
\usepackage{csquotes}
\usepackage{graphicx}
\usepackage{subfig}
\usepackage{algorithmic}
\usepackage[linesnumbered,ruled,vlined]{algorithm2e}
\usepackage{float,caption}
\renewcommand{\arraystretch}{1}
\setlength{\tabcolsep}{4pt}
\usepackage{textcomp}
\usepackage{xcolor}
\def\BibTeX{{\rm B\kern-.05em{\sc i\kern-.025em b}\kern-.08em
T\kern-.1667em\lower.7ex\hbox{E}\kern-.125emX}}
\providecommand{\nr}[1]{\textcolor{red}{[{\bf #1}]}}
\newcommand{\subparagraph}{}
\usepackage[compact]{titlesec}
\usepackage{cuted}
\usepackage{makecell}
\renewcommand\theadalign{bc}
\renewcommand\theadfont{\bfseries}
\renewcommand\theadgape{\Gape[4pt]}
\renewcommand\cellgape{\Gape[4pt]}
\usepackage{hyperref}
\usepackage{lipsum} % added for text filler
\begin{document}
\lipsum[1]
\begin{multline} % equation is a slightly shorter now ...
\text{short left part} = \\
\sum_{i=0}^{\infty} \text{very, very, very ,very long right part of equation}
\end{multline}
\lipsum[2-11]
\end{document}
Ergebnis: