Pretty simple really, I just asked their "Rufus" AI shopping assistant how to get help and got this:

"To access Amazon's customer support chat, you can visit the Your Orders section or scroll to the bottom of any page and select Customer Service. From there, choose the appropriate option that addresses your question or issue, and follow the prompts to initiate the chat."

To get help, select Customer Service ." (which is a button in the chat window)

Should work fine....