eBay affiliate program is called eBay Partner Network.

Follow the link below to register:

https://partnernetwork.ebay.com/

To get commissions for promoting eBay products, you need to create a campaign in your eBay account. One default campaign is created automatically as soon as you register. However, you can create your own campaigns.

Go to your eBay Partner Network account. Click on Campaigns in the top menu. You will see the list of your campaigns:

eBay campaign ID is a 10-digit tracking code that is included in your affiliate links. This is how eBay tracks your affiliate activity and calculates your commissions.

You have to use one of your campaign IDs in the Feedigy eBay Feeds generator.

You need your eBay Campaign ID and Custom ID every time you generate new eBay product feeds.

You can save your eBay credentials in your Feedigy account and avoid entering them manually over again

Go to the Default settings > Content feeds > eBay feeds.

Add your eBay credentials to the appropriate fields and press the Update button.