Why my discovery campaigns are missing?

The data for these campaigns isn't accessible through the Google Ads API because of restrictions related to the Discovery campaign subtype product feed. If a campaign has a subtype other than Standard, it won't be visible, except when the subtype is unspecified. Google is making a transition by transforming Discovery campaigns into a new type called Demand Gen.

For more about this, please visit the articles below:

- https://groups.google.com/g/adwords-api/c/BEOq41mcBSI

- https://groups.google.com/g/adwords-api/c/9VmCpTzanPk