Unable to link Helium 10 & Amazon seller Account

I am unable to link Helium 10 and Amazon seller central account. I contacted service support but none of the steps given by them helped, they told to contact Amazon directly for some information. I don’t understand they are saying have them (developer) contact to Amazon directly. Which developer shall I ask to contact Amazon. The one who emailed me is it self a developer, why he is not contacting. I emailed him multiple times but no response. Please help me what to do.

Sending the text emailed by them below.

Your browser settings can sometimes cause sync issues and navigation problems in Seller Central. Problems may be related to the build-up of browser cookies, cache, and history. Please take the following actions, which often resolve the problems:

1. Clear cookies, cache ("temporary Internet files"), and history. You can do this in Internet Explorer by selecting "Tools" from the top menu > Internet Options > General tab.

2. Ensure that your browser is set to accept cookies.

3. Reboot your computer.

4. Try to log into your app and seller account again and retest the sync.

If these steps do not resolve the issue, please contact the developer with this issue, and have them take a look at it. If they are unable to resolve your issue, please have them contact Amazon directly, and ask them to provide us with the following information (all that is applicable)

• Application id

• Full request and response of the failed call, done via Postman, attached to the case in txt/doc file format

• API and Operation

• Feed Id/report Id (also sometimes called Batch Id) if the issue is related to Feeds /Reports

Kindly, help me i am badly stuck in this since 1month i am following up but not getting the exact solution.