I want to document this problem and provide a solution hopefully when the solution happens, in hopes it might help someone else in the future. If you have any ideas, I am open to try them.
I created a professional Amazon Seller account. After receiving my welcome emails I attempted to connect my Amazon Sales Channel in Shopify Admin to my Amazon Seller Central account. When I click on the Connect to Amazon, everything loads up fine. Modals pop up for me to login, and everything goes great. Then Shopify Amazon sales channel re-loads the page with the following error.
Couldn’t access your Amazon account
Confirm Shopify has access from the Amazon MWS developer permissions section of Seller Central. It can take up to 12 hours for Amazon to confirm access.
In Amazon, everything looks great. Amazon says I am ready to start selling. In the Third Party Apps section under User Permissions in Amazon Seller Central the "Sale on Amazon by Shopify" app is activated and appears to be in good working order and ready to go.
The following solutions have been attempted:
1. I tried to click renew button in Amazon Seller Central
2. I clicked the disable button and then re-enabled the button
3. I deleted the Amazon sales channel from Shopify and then re added it.
4. I attempted to login again and make it force re login from shopify side about 5 times to the Amazon Seller Central account.
----------Then I called Shopify Support number 1 --------------------
1. Got suggestion to wait the 12 hours it suggested in Shopify documents for Amazon to do something magical to fix all my problems....I waited 48 hours for good measure...Nothing happened.
-----------Called Shopify Support number 2 ---------------
1. Ran through all of the above possible solutions again while on the phone...nothing changed
2. Double checked that Amazon was in good standing and ready to go. Confirmed again that Amazon account was good to go
3. Suggested by support to wait 48 hours from creating professional account. Waited 120 hours...Nothing changed.
-----------Emailed Shopify to let them know it is still not working.----------------
Currently in a waiting hold pattern. If anyone has any ideas, sound off below. When Shopify gets back to me or they escalate the issue or get Amazon involved, I'll update with the solution below in the comments when that happens. Stay tuned!
Shopify support said to clear cache and cookies. Then report issue to Amazon customer support.
Step completed, nothing changed. I explained that I worked in IT at my 8-5 job and I think I know what Amazon customer support will say "we can't help you with an error message that is showing in your Shopify Admin". I explained this and issue has been escalated to technical support.
Stay tuned folks, let see how this saga ends.