Since you didn't give more details about the problem (like what compiler are you using), it is hard to found out what is the problem. However, I have reorganized your code, maybe it solves your problem:
\documentclass[a4paper,12pt]{report}
\usepackage[table,xcdraw]{xcolor}
\usepackage[backend=biber, natbib=true, maxcitenames = 2, style=authoryear, uniquename=false]{biblatex}
\usepackage{algorithm}
\usepackage{caption}
\usepackage{amsmath,amsfonts}
\usepackage{smartdiagram}
\usepackage{float}
\newcommand{\argmin}{\arg\!\min}
\smartdiagramset{circular distance=4cm,
font=\normalsize,
text width=2.5cm,
arrow line width=0.2cm
}
\newsavebox{\mybox}
\savebox{\mybox}{%
\smartdiagram[circular diagram]{Insured \\ policy holder,Insurer \\ company}
}
\addbibresource{bib/literature.bib}
\begin{document}
your text
\printbibliography
\end{document}
Best Answer
The file is probably open in another program. Close the file and try it again.