Email address to contact a real person and not a bot

We have had a case open since August 2019 in regards to overcharges referral fees and we just keep getting the same message of

"Hello from Amazon Selling Partner Support,

We are currently investigating this issue.

We will update you as soon as additional information is available.

Thank you for selling with Amazon. "

As this case has been open for 6 months without any progress does anyone have any contact information for someone who could get this resolved please?

Thank you