Definition counter resetting on new section

I encountered this behavior from LaTex: last definition from section 2.1 was labeled (correctly) as 2.1.8. Then, the first definition of the next section was 2.2.9. I would like it to be 2.2.1 (don’t know the standards but that makes much more sense to me). I found this question which is kinda relevant but works with theorems and not definitions.

The only commands(I think) that modify somehow the definitions are:

newtheorem{definition}{MyDef}

renewcommand{thedefinition}{arabic{chapter}.arabic{section}.arabic{definition}}

So, how do I change it? Thanks in advance.

documentclass{report}

newtheorem{definition}{Definition}[section]
begin{document}

chapter{chapter}
section{first section}

begin{definition}
first definition in first section
end{definition}

begin{definition}
second definition in first section
end{definition}

section{second section}

begin{definition}
first definition in second section
end{definition}

end{document}