A new campaign data import validation report has been introduced in Google Analytics 4 to assist advertisers in verifying and improving the quality of their campaign data imports.
This report aids in assessing non-Google campaign data and imported campaign data, such as Microsoft Advertising, enabling users to identify campaigns that lack essential performance metrics such as cost, clicks, and impressions.
Additionally, the validation report allows for a review of previously imported campaign data, helping advertisers make informed decisions about their campaigns.
You can read the official announcement here: New Campaign Data Import Validation Report Launched.