Hello all,
I think you are trying to place a
getRequestToken via private app on Etsy that Etsy account which is not created on same developer acoount.
In simple words
-> If you have private Etsy app , then you can only request api's on shops created with same Developer account.
If you are getting this issue via public Etsy app, plz let me know in details the request data and headers. I may help you in this regards.
Thanks