API Error 709 When Updating Tags of an Existing Marketo Program

Issue

• Per our developer page: https://developers.marketo.com/rest-api/assets/programs/#update, it is possible to update tags on your existing program
• When updating a program tag within an existing program, you may encounter an error below given the tag and its values are correct. 

  {"code": "709","message": "Required tags are mandatory"}]}

Environment

• Any API clients when performing the Web Service API

Solution

• The workaround is to have the tag updated via the UI.

Root Cause

• "Updating tags is a destructive operation."
• Any attempt to update the tags of a program must include valid values for all of the required tags for a program.
• Unless the 'specific' tag type you are working on is the only required tag type in the instance, then that is possible to update it using the API. Otherwise, you'll encounter the error above as it is a system behaviour.