Unable to track custom events by platform (iOS app, iOS web, desktop, android web) in Branch.io, how can this be fixed?

When comparing by platform (iOS app, iOS web, desktop, android app, android web) in Branch.io in order to know where the results are coming from across the different ad platforms (Facebook, Google Ads, etc.), the total impressions by ad platform get attributed to a “-“ platform whereas the custom events (we currently track sign up and orders that are sent to Branch.io from Amplitude) are attributed to “OTHER” and it's only clicks, web sessions start, installs and opens (from my selected metrics) are attributed to the different platforms. Any suggestions on how this can be fixed?

My expectations is that I will be seeing Google Ads, Facebook Ads, Organic, etc. impressions, clicks, installs, sign ups, orders, cost... for every platform: - iOS app - iOS web - Desktop web - Android web - Android app