 Re: Unable to revise listing.. "Call us at..."
As mentioned, it's typically due to eBay not "knowing" you. Like using a new computer, logging in, and immediately trying to do a major action like listing or revising an auction. They basically are suspicious that that someone unauthorized may be using the account.
It's one of the most annoying situations to deal with. Personally I've never had it go away on it's own, but still before trying anything else I'd say it's best to take Dmshark's advice and just wait it out (actually that's good advice for a lot of eBay/Paypal related problems).
If it persists then there's a few ways that I know of that can fix it.
The very first time I had this happen, I simply called that number, gave them the security code and then they wanted to verify some basic info on the account (name, address, and phone). Then they wanted to do one more step to finalize - send a pin to the phone number they had on file. At that time I didn't have the original phone. I'm sure things would be different in the UK, but for the US the next step was for them to try and pull up questions from public records. Since this is a stealth account I knew letting them do so would be a bad idea, so I quickly asked if using my old desktop would fix the problem, the rep said yes, and I said I'll do that, thanked her and hung up before calling again.
I immediately called back and the call started off, and ended exactly the same. Finally the third time, the rep was a bit nicer when I said I changed phone numbers, and unlocked the account after she asked the basic questions about my account (name, address, and phone).
Then it happened again for a 2nd time, but on a different account. I learned from my mistake the first time and had the original phone ready (this is a TRS account so it was not something I felt the need to cut corners on), and it was easily fixed by calling the number eBay provided, and then reading back the pin number the rep sent to my phone.
And the 3rd time (again on a different account), I fixed it by simply using the old computer that I usually accessed my account from. At that time I preferred using VPSs to access my accounts and I was in the middle of moving from one VPS provider to another. Thankfully I hadn't cancelled the old VPS yet, and I simply went into the old VPS, copied over the cookies and everything was great from there (this is why I use portable browsers now - it's very easy to just copy and paste the entire folder over to a new computer and keep cookies intact).
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