Just a few things to add to all the fantastic information that the countess has given you.

Apart from changing your details, passwords etc :

Be sure to run all your spyware, keylogging and virus protection.

The scammer will give all your information to other scammers.

This information will be stored, to use at a later date.

The next scam may  actually come from a genuine eBay user ID, but the account may have been hijacked by a scammer.

The next scam may not involve apple gift cards.

It may say your payment's on hold  and will be released when  you've given them a tracking number.

DO NOT confuse this with eBay's payment hold for new sellers.

As recommended by the countess, I also agree that you should remove  all your listings until you know more about selling on eBay.

Then start with selling cheap items.  Start afresh.

You haven't sold anything for a long time  so  eBay will treat you as a new seller.

Have you actually registered to sell and signed up for managed payments ?

https://www.ebay.com.au/help/selling/getting-paid/registering-seller?id=4792&srsltid=AfmBOopqSBL0bVdnDuv6Bhnrc9027TVJAXeZ-QAMX_1NkLqWuhdzJvK9

As said - SCAM to the max.

You've done the right thing by cancelling that gift card - but this whole scenario threw up red flags from the start.

This post is going to be a bit on the lengthy side…

• If someone tries to take the sale off-eBay - irrespective of the reason - it’s a violation of eBay policy; it negates seller protection, and renders you vulnerable to eBay sanctions as well as the actual scam in progress. This is a red flag.
• The buyer claiming they have no access to their eBay account is patently nonsense - and even if it weren’t, that would mark the buyer as a risk. This is a red flag.
• If the buyer had no access to their eBay account, how on earth are eBay involved in the so-called payment? Red flag.
• The eBay profile re the video of “product” is probably an attempt to get a video of gift card - so that they can see the numbers to access the funds of the gift card. Red flag.
• The mention of an Apple gift card is a classic, classic sign of a scam. Red flag is practically burning your eyeballs at this point.
• The email faked to look as though it’s from eBay, with the telltale gmail address, is a red flag. You should know how eBay notifies sellers of payment. Not in your Seller Hub? Then it’s not been paid - and as already stated, if the buyer hasn’t access to their eBay account, it’s as obvious as a pregnant camel having quintuplets that payment can’t be through eBay. Red flag red flag red flag.
• Pushiness trying to hurry you with false sense of urgency, not letting you have a moment to think rationally - red flag.

Right. Yes, this is a scammer.

The bad news is that you’ve given the scammer a lot of information about yourself. The scammer definitely knows your email address. Scammer may know your full name, possibly phone number, some details about you… password hints? Did they ask about first beach you visited, first car, favourite pets? They can match up any data from your eBay account to your email address. They may know your bank. All of this information can be put together like a jigsaw puzzle to make you a target for identity theft.

They also know you are vulnerable to further scams, because you got right to the edge of the cliff with this one. You will undoubtedly be subjected to further scam attempts. Be suspicious and hyper-aware. If a so-called fraud detection organisation contacts you, be vigilant; that could be another scam.

Re eBay - take down your listings until you know more about selling on eBay, because at the moment you do not know enough to protect yourself but for the grace of God and your spidey senses tingling (thank goodness!) The responders on these boards can help by pointing you in the right direction with eBay policy pages and help pages, and explaining some of the pitfalls. I very strongly do suggest you take a step back with listing until you have read and understood the relevant pages… I’m just very glad you did come to these boards to express your concerns and did cancel the gift card.

Re dealing with the issue of any information you have imparted to the scammer, don’t post the actual information here (no names or addresses etc), but what does the scammer know at the point?

1. Full name?
2. Address?
3. Email address?
4. Possibly thus also PayPal email address?
5. Possibly thus also email for myGov account?
6. Phone number?
7. Social media accounts?
8. Bank?
9. Bank account information?
10. Any information that might help with password hints?

There are things you can do to protect yourself; you may want to change the settings for some accounts, and it may be a good idea to go in personally to your bank and see what they can suggest. Go in to your telco personally as well and take steps to prevent phone porting.

Create completely separate email account for your eBay account, but don’t close the other email account at this point… You probably still need access to it, anyway - but do be cautious of emails as I would anticipate lots of scamming ones from now on.

Once you’re more on top of things, you’ll know what not to do, especially when selling an expensive item on eBay. (You may also want to start slow with selling - try selling low-value items to build up feedback and not look like a new and potentially ignorant seller to scammers. Perhaps buy some small items also to get the shiny new look off your feedback score…?)

for starters, eBay don't use Gmail email address.

SCAM

Do as sandy says and stop all communications with them.  Delete future messages from them without reading them as they are very good at convincing people they are genuine.

The very second they mention gift card, they have outted themselves as a scammer

Stop communicating with the so and so, and block them

They are trying to take advantage of your inexperience as a seller and hope to trick you

Report them to eBay if you can

Block, block, block

And eBay does not have a gmail address

Fake as a flying cow