Hi guys!

I'm having problems to associate an stakeholder to a B2B opportunity. 

In the New opportunity form, I'm trying to associate an existing stakeholder to my opportunity, but I can't. After choosing the Sales Account value, the Stakeholders section shows me all the contacts associated to that account. However, when I choose one, the form shows me an error that says "This contact does not exist". When this happens, Create button locks itself and I'm not be able to create the opportunity.

Checking the clipboard, I found the following error:

** One last thing, I don't have permission to work from App Studio, all is being modified from rules in Dev Studio.

Could you help me with this error, please? What do I need to modify to solve this error? 

Thank you in advance! :)

Regards.