Here is my regular expression. In my case, there are 2 spaces right after the regular expression for the time parameter. Those characters are omitted to one space in the Configuration section.
^(?<time>\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}.\d{3})Z (?<log_level>\w+) \[(?<module>\w+)\] (?<message>.*)