The instruction here may not be entirely up-to-date, but should allow you to request a call back if followed generally:
https://community.ebay.com/t5/Selling/How-do-I-contact-Customer-Support/m-p/32016431#M1783851
Basically you need to get to the chat assistant, and then use that to request a chat with an agent. You may need to provide some context-dependent cues to see the agent option.
