As you are utilizing your Twitter Ads | Line Item Standard Dataset and Twitter Ads | Promoted Tweet Standard Dataset, you will notice that you are not seeing ads in the Promoted Tweet Standard Dataset.
This is due to how the Twitter Ads API splits up the paid media types. The Promoted Tweet Standard Dataset will only include tweets that you have promoted while the Line Item Standard Dataset will include ads and promoted tweets. The API considers the line item endpoint to be a catch-all for all paid media types at the ad group level, but does not provide a catch-all endpoint for all paid media types at the ad level. For this reason, we are unable to pull ad level data specifically for ads.
If you have further questions about your data, please reach out to Support.