Select this policy assertion as described in Adding Policy Assertions.

For performance reasons, a reply activity matching a receive, as well as synchronous invokes, are timed out if they do not execute on Process Server within 10 minutes. If you are receiving timeout errors, you can specify a greater amount of time to wait before a process is timed out due to a reply or synchronous invoke activity not executing within 10 minutes. The default is 600 seconds.

Enter a time out value in seconds. A value of zero indicated unlimited wait time.