ICampaignManagementService do not returns campaigns with bidding strategy Manual CPM (C#)

Question

We were using ICampaignManagementService to get campaigns report. But it does not return Audience campaigns with bid strategy / bidding scheme as Manual CPM. As soon as we shift bidding strategy from Manual CPM to something else, the campaigns show up in the report.

But when using bulk api, we get these campaigns in report.

The api does not support campaigns with Manual cpm bid strategy?
If that's the case, then only GetCampaignsByAccountIdRequest not gives result for these campaigns or all other reports like GetBudgetsByIdsRequest, GetSharedEntitiesByAccountIdRequest also does not support these campaigns?