That's odd they're not responding. Each time I've reported a competitor (she's too lazy to write her own stuff, occasionally steals from me), they've written back asking for facts (dates) etc.
I report this way - once to Canadian regular help, once to the .com regular help, then again to PS support. Probably all goes to the same queue, but usually I get at least one response.
Live Help (if available) should be on the splash page.
*JMHO* - to be taken with a grain of salt!