Best contact for possible fraud / missing deliveries / gps?

[pepsi_max2k]

Hey all, eBay seller here. Have a customer of mine with a just-slightly-plausible bunch of missing RM deliveries.

Supposedly, they live in a somewhat complex housing layout (confirmed via google, it's a nightmare, HG3 2UA), and every recent purchase they've made from anyone hasn't shown up (not the most likely event under any circumstances). In addition, Recorded mail isn't getting scanned at all. So anyway I figure one of the following is happening:

1. They're scamming everyone they purchase from. That's usually the case. But they phoned up and sound just about nice enough to bother looking further in to, so...
2. The postie is pocketing all their items. Not likely, but I know RM like to look in to this.
3. The postie is delivering to a differing address (example: 10 Bleh instead of 10 Blah, basically around the corner, but there isn't really a corner as it's a sort of elderly / uni halls style grassy complex - so, plausible, except residents at 10 Bleh know nothing)
4. The postie isn't delivering at all, and they're being held at sorting office until returned to sender (and someone couldn't be bothered to scan at delivery office).

So anyway, who's the best person to contact? Delivery Office? (apparently buyer has tried there and they know nothing either... a lot of nothing everywhere...). General CS? (they usually send me an auto reply). Fraud guys? (on basis it could be a scam by someone, I think I have a direct email for them somewhere). Or anyone know a manager or someone at applicable delivery office who could take a look / check with postie what's going on? Or try and get customer to contact someone (like I say, apparently they have, but either got nowhere, or are making everything up).

Thanks anyway,

Christopher

[A2B]

If you're on Twitter ask at @RoyalMail they tend to sort things quickly when the world is watching

[pepsi_max2k]

Will try. Same buyer's now supposedly had a tracked item, showed collected from delivery office, reported as missing - apparently it was "someone else" who collected it. With ID and the actual correct address, of course... Needs to go straight to the fraud team I recon :)

[A2B]

Personally i would still go with the Twitter account with a message like "who do i contact regards missing/stolen mail in the ??? ??? postcode?" and i would expect a swift response