How to create asynchronous calls in sequence diagram?

Question

I am using tikz-uml to create a UML sequence diagram. The sequence involves the object's life to die after an asynchronous call is made, and then it gets alive again after the response is got. Something like this:

However, i cannot recreate the same thing in in LaTeX TikZ-UML. This is what i get instead.

Here is my MWE.

\documentclass{article}
\usepackage{tikz-uml}
\begin{document}
\begin{tikzpicture}
\begin{umlseqdiag}
\umlactor[no ddots]{user}
\umlobject[no ddots]{web}
\umlobject[no ddots]{DB}
\begin{umlcall}[op={\-}, return={\-}]{user}{web}
\begin{umlcall}[op={receive\_request}, return={send\_request}]{web}{DB}
\end{umlcall}
\end{umlcall}
\end{umlseqdiag}
\end{tikzpicture}
\end{document}

How to end the object life and start the object life in between? They are simply asynchronous calls.