Hi, Since you mentioned that the third account is already under your MCC account, the other reason that you are encountering the AuthorizationError.USER_PERMISSION_DENIED <https://developers.google.com/adwords/api/docs/common-errors#AuthorizationError.USER_PERMISSION_DENIED> error could be due to using OAuth2 credentials that has no access to the client account that you are using as your clientCustomerId.
This being said, could you provide the complete SOAP request and response that was generated when you encountered the error? You may send the SOAP logs privately via the *Reply privately to author* option. If you haven't enabled SOAP logging, let me know which client library you are using so that I can provide you the appropriate guide to enable it. Thanks and regards, Peter AdWords API Team -- -- =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~ Also find us on our blog and Google+: https://googleadsdeveloper.blogspot.com/ https://plus.google.com/+GoogleAdsDevelopers/posts =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~ You received this message because you are subscribed to the Google Groups "AdWords API Forum" group. To post to this group, send email to adwords-api@googlegroups.com To unsubscribe from this group, send email to adwords-api+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/adwords-api?hl=en --- You received this message because you are subscribed to the Google Groups "AdWords API Forum" group. To unsubscribe from this group and stop receiving emails from it, send an email to adwords-api+unsubscr...@googlegroups.com. Visit this group at https://groups.google.com/group/adwords-api. To view this discussion on the web visit https://groups.google.com/d/msgid/adwords-api/e4669d6f-6c32-4a59-a896-b3d59ce3bb99%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.